CBSE Class 12 Economics Producer Behavior and Supply Assignment

POINTS TO REMEMBER

❑ Total production refers to the sum total of production done by using all units of variable factors over a given period of time.
❑ Average production is the per unit output of variable factor (labour) employed.
AP = TP variable input
❑ Marginal product is addition to total product resulting from employing one additional unit of variable input.
❑ Returns to a factor : In a short period when additional units of variable factors are employed with given fixed factors, then returns to a factor operates. Returns to a factor shows the changes in total products, marginal product which arises due to change in ratio between fixed and variable factor.
They are as follows :
(A) Increasing returns to a factor : In the initial stage as more and more units of variable factor are employed with fixed factor total physical production increases at increasing rate.
(B) Diminishing returns to a factor : As more and more units of variable factors are employed with fixed factors, then total product increases at diminishing rate.
(C) Negative returns to a factor : This is the last stage of returns to a factor. As more and more units of variable factors are employed with given fixed factors, total production starts decreasing and marginal product becomes negative.

Relation between Total, Average and Marginal Product
1. So long as marginal product rises, total product increases at increasing rate.
2. Marginal product starts falling but remains positive, total product rises at diminishing rate in this stage.
3. When marginal product becomes negative, then total product starts falling in this stage.
4. So long as average production is less than marginal product, average production increases Marginal product intersects average product at the point where average product is maximum. After this average product
starts falling and is more than marginal product in this stage.
❑ Cost : Cost is the sum of direct (explicit cost) and indirect cost (implicit cost).
❑ Those monetary payments, which are incurred by producers for payment those of factor and non-factor inputs which are not owned by produces are called Direct Cost.
❑ Implicit cost is the cost of self owned resources of the production used in production process.

❑ Total cost is the sum of total fixed cost and total variable cost.
TC = TFC + TVC or TC = AC X Q
❑ Total fixed cost remains constant at all levels of output. It is not zero even at zero output level. Therefore, TFC curve is parallel to OX-axis.
TFC = TC – TVC or TFC = AFC × Q
❑ Total variable cost is the cost which vary with the quantity of output produced.
It is zero at zero level of output. TVC curve is parallel to TC curve.
TVC = TC – TFC or TVC = AVC × Q
❑ Average cost is per unit of total cost. It is the sum of average fixed cost and average variable cost.
AC = TC
or AC = AFC + AVC
❑ Average fixed cost is per unit of total fixed cost.
AFC = or AFC = AC – AVC
❑ Per unit of total variable cost is called average variable cost.
AVC = or AVC = AC – AFC
❑ Net increase in cost for producing one additional unit is called marginal cost.
MC_n = TVC_n – TVC_n–1 or MC = TFC/Q

Relation Between Short-Term Costs
❑ Total cost curve and total variable cost curve remains parallel to each other. The vertical distance between these two curves is equal to total fixed cost.
❑ TFC curve remains parallel to X aixs and TVC curve remains parallel to TC curve.
❑ With increase in level of output, the vertical distance between AFC curve and AC curve goes on increasing. On contrary the vertical distance between AC curve and AVC curve goes on decreasing but these two curves never intersect because average fixed cost is never zero.
❑ Marginal cost curve intersects average cost curve and average variable cost curve at their minimum point. After the point of intersection with increase in output, AC curve and AVC curve starts rising.
❑ MC curve remains under the AC and AVC curve before inter section point but after inter section point AC and AVC curve remains under the MC curve.
❑ Average cost and average variable cost falls till they are more than marginal cost. When these two costs are less than marginal cost, in that situation both (AC and AVC) rise.
❑ Money received from the sale of product is called revenue.
❑ Total revenue is the amount received from the sale of given units of a commodity over a particular period of time.
TR = AR × Q or TR= SMR
❑ Per unit revenue received from the sale of given units of a commodity is called average revenue. Average revenue is equal to price.
AR = TR/Q or = P = Price.
❑ Marginal revenue is net addition to total revenue when one additional unit of output is sold.
MR = ΔTR/ΔQ    PXQ/Q
❑ Behaviour of TR, AR and MR when per unit price remains constant or firm can sell additional quantity of a good at same price
(a) Average revenue and marginal revenue remains constant at all levels of output and AR and MR curves are parallel to ox-axis.
(b) Total revenue increases at constant rate and TR curve is positively sloped straight line passing through the origin.
❑ Behaviour of TR, AR and MR when price falls with additional unit of output sold or there is monopoly or monopolistic competition in the market
(a) Average revenue and marginal revenue curves have negative slope.
MR curve lies below AR curve.
(b) Marginal revenue falls, twice the rate of average revenue.
(c) So long as marginal revenue is positive, total revenue increases. When marginal revenue is zero, total revenue is maximum and when marginal revenue becomes negative, TR starts falling.
❑ Concept of Producer’s Equilibrium : If refers the stage where producer getting maximum profit.
(A) MR and MC Approach : Conditions of producers equilibrium according to this approach are :
(a) Equality between MR and MC
(b) MC curve should cut the MR curve from below at the point of equilibrium.
Or
MC should be more than MR after the equilibrium point, with increase in output.
❑ Supply : Refers to the amount of the commodity that a firm or seller is willing to offer or to sell in a given period of time at various prices.

❑ Individual Supply : Refers to quantity of a commodity that an individual firm is willing and able to offer for sale at each possible price during a given period of time.
❑ Stock : Refers to the total quantity of a particular commodity available with the firm at a particular point of time.
❑ Supply Schedule : Refers to a tabular presentation which shows various quantities of a commodity that a producer is willing to supply at different prices, during a given period of time.
Supply curve : Refers to the graphical representation of supply schedule which represents various quantities of a commodity that a producer is willing to supply at different prices during given period of time.
❑ Law of Supply : States the direct relationship between price and quantity supplied, keeping other factors constant.
Exceptions to Law of Supply
1. Future Expectation
2. Agricul
3. Perishable goods
4. Rare goods
5. Backward countries.

❑ Price Elasticity of Supply : Refer to the degree of responsiveness of supply of a commodity with reference to a change in price of such commodity.
It is always positive due to direct relationship between price and quantity supplied.

Price Elasticity of Supply (Es) = Percentage change in quantity supplied/Percentage change in price

❑ Methods for measuring price elasticity of supply :
1. Percentage Method 2. Geometric Method

❑ Degrees of Elasticity of Supply :
(a) If the tangent to the supply curve passes through the point of origin, Es at that point is equal to unity.
(b) If the tangent intersects the x-axis, Es at that point is less than unity
(c) if tangent intersects the y-axis Es at that point will be greater than unity.

Very Short Answer Type Questions

Question. Define production function.
Answer: Diminishing return to a facter

Question. Define marginal product.
Answer: Marginal product is net addition to total product when one additional unit of variable factor is used.

Question. What will be the behavior of total product when marginal product of variable input is falling but is positive?
Answer: Total product increases at diminishing rate.

Question. What is the relation between average and marginal product when average product is falling?
Answer: MP falls but it falls at faster rate than AP

Question. Define average production.
Answer: AP is a per unit output of a variable factor.

Question. What do you mean by fixed factors of production? Give example.
Answer: These factors of production which cannot be varied in short period e.g. machine, land.

Question. By which behaviour of marginal product will total product be maximum.
Answer: When marginal product of a factor is zero, then total product will be maximum. 

Question. How does fall in total product affects marginal product?
Answer: When total product falls, marginal product becomes negative.

Question. What do you mean by cost?
Answer: Cost is the sum of explicit and implicit cost.

Question. Define explicit costs.
Answer: Those monetary payments by producer on factor and non factor payments is called explicit cost. Which are not owned by himself.

Question. Which cost curve is parallel to ox-axis? Why?
Answer: Total fixed cost because TFC remain constant at all level of output.

Question. What do you mean by implicit costs?
Answer: Implicit cost is the cost of self owned resources of producer.

Question. Define marginal cost.
Answer: Marginal cost is the net addition to total cost when one additional unit of output is produced.

Question. Why does the difference between average total cost and average variable cost falls with increase in output?
Answer: It is because average fixed cost goes on falling with increase in output.

Question. Define Revenue.
Answer: Revenue is the amount received from sale of output.

Question. At what rate average and marginal revenue falls, with fall in per unit price of a good?
Answer: Marginal revenue falls twice the rate of average revenue.

Question. What will be the behaviour of Average revenue when total revenue increases at constant rate?
Answer: Average revenue remains constant.

Question. What do you mean by marginal revenue?
Answer: Marginal revenue is net additions to total revenue by sale of one additional unit of output.

Question. What will be the behaviour of total revenue when marginal revenue is zero?
Answer: Total revenue will be maximum.

Question. Why does average cost curve and averages variable cost curve never intersect each other?
Answer: Because AFC can never be zero at any level of output.

Question. What do you mean by producer’s equilibrium?
Answer: Producer’s equilibrium is a situation where he gets maximum profit.

Question. State any two conditions of producers equilibrium according to marginal revenue and marginal cost approach.
Answer: 1. MR = MC
2. Rising portion of Marginal cost curve intersects marginal revenue curve.

Question. Define Market Supply
Answer: Supply refers to the amount of the commodity that a firm or seller is willing to offer for sale in a given period of time at various prices.

Question. Name two determinants of supply.
Answer: Individual supply schedule is a tabular representation showing various quantities of a commodity which a firm is ready to sell at different prices during a given period of time.

Question. What is meant by change in supply?
Answer: It referes the sum of tatal quantity supplied by all the firms in a market.

Question. What type of change in price is the cause of upward movement along a supply curve?
Answer: 1. Number of firms
2. Change in technology

Question. What effect does an increase is tax rates have on supply of a commodity?
Answer: Change in supply refers to increase or decrease in supply of a commodity due to change in factors other than price like technology, price of inputs, Goal of producer, Number of firms etc.

Question. What causes a downward movement along a supply curve?
Answer: Due to increase in price.

Question. What is meant by leftward shift of supply curve?
Answer: As a result of increase in tax rates production cost increase, so the profit margin of producer will fall and producer will decrease the supply.

Question. How does a decrease in price of input effect supply curve of the commodity?
Answer: Decrease in price.

Question. Why does a supply curve have a positive slope?
Answer: Due to change in other factors the supply of a commodity falls at same price than supply curve shifted to leftward.

Question. What is meant by elasticity of supply?
Answer:  As a result of decrease in price of input production cost falls then producers profit margin will increase so producer will increase the supply of commodity.

Question. What is the price elasticity of supply, if supply curve is parallel to y-axis.
Answer: Because of positive relation between price and supply.

Question. When does the elasticity of supply of commodity called equal to unity?
Answer: Price Elasticity of Supply (Es) is a measure of degree of response of supply for a good to change in its price.

Question. When does the producer increase the supply of a good at given price, give two reasons.
Answer: Perfectly elastic.

Question. What causes an extension in supply?
Answer: When percentage change in price is equal to percentage change in supply.

Question. If the price of a commodity falls by 10% and, consequently, the quantity supplied decreases by 20%. What will be its price elasticity of supply?
Answer: Due to change in other factor like improvement in technology, decrease in price of inputs.

H.O.T.S.

Question. Why is total variable cost curve parallel to total cost curve?
Answer: Increase in price of a commodity.

Question. Why does average fixed cost fall with increase in output?
Answer: Es = % change in quantity/% change in price = 20%/10% = 2

Question. Why is total fixed cost curve parallel to ox-axis.
Answer: Total cost is the sum of total fixed cost and total variable cost. 

Question. Under which situation will MR fall when an additional quantity of a good is sold?
Answer: TFC remains constant at all levels of output.

Question. What behaviour of per unit price will cause the equality of average and marginal revenue.
Answer:When per unit price falls by selling an additional unit of a good.

Question. Give one differences between law of supply and price elasticity of supply.
Answer: Per unit price remains constant.

Question. What is the price elasticity of supply associated when the supply curve passing through to intersect to x-axis?
Answer: Law of supply reflects the direction of change in supply where as price elasticity of supply measures the magnitude of change in supply.

Question. Why does a producer moves downward along a supply curve due to decrease in price of commodity?
Answer: Inelastic.

Question. What is the price elasticity of supply associated with when a supply curve passes through the origin at 40° angle?
Answer: Because profit margin of firm (producer) decreases.

Question. When does the supply curve shift rightward while price remains constant.
Answer: Equal to unity elastic.

Question. What effect does an increase in price of competitive good have on the supply of a commodity?
Answer: When the supply of commodity increases due to change in other factors.

Question. How does the imposition of a tax affect the supply curve of a firm?
Answer: Supply of the commodity will fall.

Key Points for Class 12 Economics Chapter 04 The Theory of the Firm under Perfect Competition

Producer Behavior and Supply

Production Function: Return to a Factor and Return to Scale

Question 1. what is production?
Answer: Production is the process of converting input materials and resources into finished goods and services.
In simple words: Production means taking raw materials and turning them into useful products.

Exam Tip: Define it as the creation of utility or transformation of inputs into outputs.

Question 2. Transformation of inputs into output what is called for That?
Answer: This transformation process is called production.
In simple words: Turning inputs into outputs is what we call production.

Exam Tip: Keep the answer brief and use the term "production" directly.

Question 3. what are necessary inputs for production?
Answer: The inputs required for production include factor inputs, like land, labor, capital, and entrepreneurship, as well as non-factor inputs like raw materials.
In simple words: To make things, you need workers, machinery, land, and raw materials.

Exam Tip: Classify these inputs into factor and non-factor categories to show a thorough understanding.

Question 4. Inputs which a producer or a firm acquires for the Process of production?
Answer: The inputs acquired by a firm for production are categorized as factor inputs (such as machinery and labor) and non-factor inputs (such as fuel and raw materials).
In simple words: These are the components, materials, and services a business buys to manufacture its products.

Exam Tip: Mention both categories of inputs to ensure your answer is complete.

Question 5. What are factor inputs?
Answer: Factor inputs are the primary agents of production, which consist of land, labor, capital, and entrepreneurial skills.
In simple words: Factor inputs are the main resources needed to run a business, like workers and machinery.

Exam Tip: List the four classical factors of production to get full marks.

Question 6. What are non factor inputs?
Answer: Non-factor inputs are auxiliary materials, such as raw substances, power, and fuel, which get completely consumed during the production process.
In simple words: These are things like raw wood or electricity that get used up when making a product.

Exam Tip: Note that non-factor inputs do not yield services over multiple production cycles, unlike capital.

Question 7. What is the process of production?
Answer: The process of production is the technical transformation of raw inputs and factor services into finished outputs.
In simple words: It is the step-by-step way a business turns ingredients or parts into a finished item.

Exam Tip: Focus on the technical and physical transformation aspect of this definition.

Question 8. Express the relationship between inputs used and output produced by a firm.
Answer: The physical relationship between the inputs used and the resulting output of a firm is expressed through the production function: \[ Q = f(X_1, X_2, X_3, \dots, X_n) \] Here, \( Q \) represents the total quantity of output, and \( X_1, X_2, \dots \) represent the quantities of different inputs.
In simple words: This relationship is shown by a mathematical formula that tells us how much product we get from a certain mix of inputs.

Exam Tip: Write down the mathematical equation of the production function to earn full marks.

Question 9. What are factors of production?
Answer: Factors of production are the resources required to generate goods and services, traditionally grouped into land, labor, capital, and enterprise.
In simple words: These are the basic building blocks used to produce any kind of product or service.

Exam Tip: Memorize the four factors: Land, Labor, Capital, and Enterprise.

Question 10. Which factor whose quantity may be changed as the level of output changes. Give example.
Answer: A variable factor is one whose quantity can be adjusted in response to changes in the volume of output. For example, raw materials and casual labor are variable factors.
In simple words: Variable factors are resources you buy more of when you want to make more products, like wood for furniture.

Exam Tip: Always provide a clear, real-world example like raw materials or temporary labor.

Question 11. What are variable factors?
Answer: Variable factors are those inputs whose employment levels change directly with the level of output produced by the firm.
In simple words: These are the inputs that a business can easily increase or decrease as production levels go up or down.

Exam Tip: Differentiate them from fixed factors, which cannot be changed in the short run.

Question 12. In which period all the factors can be changed?
Answer: All production factors can be modified and adjusted during the long-run period.
In simple words: In the long run, a company has enough time to change all of its resources, including building new factories.

Exam Tip: Keep your answer brief and name the "long run" explicitly.

Question 13. Which factor whose quantity cannot be changed as the level of output changes. Give example.
Answer: A fixed factor is an input whose quantity remains constant regardless of changes in the level of output. Examples include factory land, heavy machinery, and permanent buildings.
In simple words: Fixed factors are assets like factories or heavy machines that you cannot easily change quickly, even if you make more or less product.

Exam Tip: Use factory buildings or heavy machinery as standard examples.

Question 14. What are fixed factors?
Answer: Fixed factors are production inputs whose quantities cannot be altered in the short run, even if the firm's level of output changes.
In simple words: These are inputs that stay the same size or quantity in the short run, regardless of how much output is produced.

Exam Tip: Emphasize that fixed factors only exist in the short run.

Question 15. What is short run and long run period?
Answer: The short run is a time period where at least one factor of production is fixed, while others are variable. The long run is a time period where all factors of production are variable, and no inputs are fixed.
In simple words: The short run is when you can only change some inputs (like labor), while the long run is when you have enough time to change everything (like building a new factory).

Exam Tip: Explain that these terms refer to operational flexibility rather than calendar time.

Question 16. Can supply of the commodity be adjusted in the short run? Give reason.
Answer: Yes, supply can be adjusted in the short run, but only up to the capacity of the existing fixed factors by increasing the use of variable inputs like labor and raw materials.
In simple words: Yes, you can change supply a little bit in the short run by hiring more temporary workers or using more materials, but you cannot build new factories.

Exam Tip: Note that supply is relatively inelastic in the short run compared to the long run.

Question 17. Explain the technical relationship of production function.
Answer: The production function establishes a purely technical or physical relationship between inputs used and the maximum output produced, independent of input prices and market conditions.
In simple words: It is a technical rule showing how much physical product you get when you combine different physical ingredients and equipment.

Exam Tip: Emphasize that this relationship is purely technical and does not deal with costs or prices.

Question 18. What is production function?
Answer: A production function is a functional expression that details the maximum output possible from a specific combination of inputs over a given period.
In simple words: It is the formula or system that shows the link between resources used and the final product made.

Exam Tip: State the mathematical form \( Q = f(L, K) \) to demonstrate clarity.

Question 19. How does short run production function differ from the long run production function?
Answer: In a short-run production function, at least one input is kept fixed while others vary, reflecting the law of variable proportions. In a long-run production function, all inputs are varied in the same proportion, reflecting the returns to scale.
In simple words: The short-run version has some fixed parts (like factory size), while the long-run version lets you change everything.

Exam Tip: Contrast the "Returns to a Factor" (short run) with "Returns to Scale" (long run).

Question 20. What is the relationship between the variable input and output, keeping all other inputs constant?
Answer: This relationship is explained by the Law of Variable Proportions (or Return to a Factor). It shows that as more of a variable factor is added to fixed factors, the output initially rises at an increasing rate, then at a diminishing rate, and eventually begins to decline.
In simple words: If you keep adding workers to a fixed space, production grows fast at first, then slows down, and eventually gets crowded and drops.

Exam Tip: Name the "Law of Variable Proportions" as the governing economic principle here.

Question 21. What is the Total Product of an input?
Answer: Total Product (TP) is the total volume of goods produced by a firm during a specific period using a given quantity of variable inputs combined with fixed inputs.
In simple words: Total Product is the entire amount of goods made by the company using all its resources.

Exam Tip: Define it as the sum total of marginal products: \( TP = \sum MP \).

Question 22. How is TPP derived from APP?
Answer: Total Physical Product (TPP) is derived by multiplying the Average Physical Product (APP) by the units of the variable factor employed (\( L \)): \[ \text{TPP} = \text{APP} \times L \]
In simple words: You can find the total product by taking the average amount made by one worker and multiplying it by the total number of workers.

Exam Tip: Write down the formula clearly to show how the terms are related.

Question 23. What is APP of an input?
Answer: Average Physical Product (APP) is the output generated per unit of the variable factor employed: \[ \text{APP} = \frac{\text{TPP}}{L} \] where \( L \) is the quantity of the variable input.
In simple words: Average product is the typical amount of goods made by a single worker when you divide the total output by the number of workers.

Exam Tip: Define it as total product divided by the units of variable input used.

Question 24. What is MPP of an input?
Answer: Marginal Physical Product (MPP) is the additional output produced by employing one more unit of the variable input, while keeping all other inputs constant: \[ \text{MPP}_n = \text{TPP}_n - \text{TPP}_{n-1} \]
In simple words: Marginal product is the extra amount of goods you get when you hire just one more worker.

Exam Tip: Highlight that MPP represents the rate of change of TPP.

Question 25. How is TPP derived from MPP schedule?
Answer: Total Physical Product (TPP) is calculated by summing up the Marginal Physical Products of all the units of the variable factor used up to that point: \[ \text{TPP}_n = \sum_{i=1}^n \text{MPP}_i \]
In simple words: You get the total product by adding up the extra products made by each individual worker.

Exam Tip: Explain that TPP is the cumulative sum of the MPP values.

Question 26. When APP is at its maximum, what is the relationship between MPP &APP?
Answer: When Average Physical Product (APP) reaches its maximum point, the Marginal Physical Product (MPP) is exactly equal to the APP \( ( \text{MPP} = \text{APP} ) \).
In simple words: When average production is at its highest, the extra product from the next worker is equal to the current average.

Exam Tip: Note that the MP curve intersects the AP curve from above at the AP curve's peak.

Question 27. When only one factor is increased and all other inputs are held constant. Examine the effects on output. What happens with the marginal product?
Answer: When only one variable input is increased while others are held constant, output initially increases at an increasing rate, then increases at a diminishing rate, and eventually falls. Correspondingly, the marginal product first rises, reaches a peak, then falls, becomes zero, and eventually turns negative.
In simple words: If you keep adding just one kind of worker to a fixed office, the extra work they do goes up at first, then drops to zero, and eventually becomes negative as they get in each other's way.

Exam Tip: This question describes the Law of Variable Proportions - make sure to name and outline all three phases in your answer.

Question 28. Show the relationship between MP and AP of an Output with the help of diagram.
Answer: The relationship between Marginal Product (MP) and Average Product (AP) is as follows:
1. When MP is greater than AP, AP rises.
2. When MP equals AP, AP is at its maximum.
3. When MP is less than AP, AP falls.
4. MP can be zero or negative, but AP remains positive.
In simple words: Think of AP as your exam average and MP as your score on the next test. If your next test score is higher than your average, your average goes up. If it is lower, your average drops.

Exam Tip: Draw both curves with MP reaching its peak before AP, and make sure MP cuts AP exactly at the maximum point of AP.

Question 29. What happens to the MP curve when the TP starts declining?
Answer: When the Total Product (TP) curve begins to decline, the Marginal Product (MP) curve becomes negative (drops below the horizontal x-axis).
In simple words: When your total output starts going down, it means the last worker you hired actually reduced production, so the marginal product becomes negative.

Exam Tip: Note that MP is zero when TP is at its maximum, and becomes negative when TP falls.

Question 30. MPP can be zero and negative (-) but APP never Becomes zero. Give reason.
Answer: MPP can be zero or negative because additional workers can eventually cause overcrowding or coordination failures, leading to no extra output or a drop in total output. However, APP can never become zero as long as any total product is produced, because APP is TP divided by the number of inputs, and TP remains positive.
In simple words: Extra workers can get in each other's way and cause total output to drop (negative MP). But as long as something is being made, the average production per worker will always be a positive number.

Exam Tip: Point out that APP only becomes zero if TP is zero, which is not possible during active production.

Question 31. What is the law of diminishing marginal product?
Answer: The law of diminishing marginal product states that as more units of a variable input are employed with a fixed factor, a point will be reached where the additional output (marginal product) begins to decline.
In simple words: It is the rule that as you keep adding workers to the same set of machines, the extra goods each new worker produces will eventually get smaller and smaller.

Exam Tip: Emphasize that this law assumes technology and other input factors remain constant.

Question 32. What does the law of variable proportion state?
Answer: The law of variable proportions states that when more units of a variable input are combined with a fixed input, the total output initially increases at an increasing rate, then at a decreasing rate, and finally starts declining.
In simple words: This law explains how output changes when you increase only one input: first it grows quickly, then it slows down, and finally it starts going down.

Exam Tip: Be prepared to outline the three phases: increasing returns, diminishing returns, and negative returns.

Question 33. Identify the three phases in the Law Of Variable Proportions from the following: -

Answer: To identify the phases, we first calculate the Marginal Product (MP) for each unit:

Based on this, the three phases are:
- **Phase I (Increasing Returns):** From unit 1 to 2, where MP increases from 20 to 30.
- **Phase II (Diminishing Returns):** From unit 2 to 4, where MP falls from 30 to 10, but remains positive.
- **Phase III (Negative Returns):** Beyond unit 4 (at unit 5), where MP becomes negative (-20).
In simple words: The first two workers bring increasing extra gains. The third and fourth workers still add to production but at a slower rate. The fifth worker actually hurts production, causing total output to drop.
Exam Tip: Calculate the MP column first to clearly identify the boundaries between the three stages of production.

Question 34. Which of the stages of the Law of variable proportion is relevant for firm, which aims at maximum efficiency of profit?
Answer: Stage II (Diminishing Returns) is the rational stage of production where a profit-maximizing firm will operate, because here the marginal products of both variable and fixed factors are positive.
In simple words: A smart business owner will always operate in the second stage, where every extra worker hired still adds positive value without causing overcrowding.

Exam Tip: Explain why Stage I (underutilization of fixed inputs) and Stage III (inefficient crowd effects) are avoided by rational firms.

Question 35. What is return to scale?
Answer: Returns to scale refers to the behavior of total output when all inputs (factors of production) are increased simultaneously and in the same proportion in the long run.
In simple words: It shows how much more product we get when we double or triple everything in our business, like opening an exact duplicate of our current factory.

Exam Tip: Ensure you specify that returns to scale is exclusively a long-run production concept.

Question 36. What is called for all the factors when they are variable with the change in the level of output in the long run?
Answer: In the long run, all inputs are referred to as variable factors.
In simple words: When you look at the long run, there are no fixed costs or assets; every single input can be changed.

Exam Tip: Keep this answer short, highlighting that fixed factors do not exist in the long run.

Question 37. Make the difference between Return to a factor and Return to a scale.
Answer: The difference between Return to a Factor and Return to Scale is:
1. Return to a Factor is a short-run concept where one input varies while others are held constant. Return to Scale is a long-run concept where all inputs vary in the same proportion.
2. Return to a Factor alters the factor ratio, whereas Return to Scale keeps the factor ratio constant.
In simple words: Return to a factor is about changing one ingredient in a fixed kitchen. Return to scale is about scaling up the entire kitchen and all ingredients together.

Exam Tip: Drawing a comparison table is the best way to present this answer for full marks.

Question 38. How does Return to a factor differs from Returns to Scale?
Answer: Return to a factor operates in the short run and is governed by the Law of Variable Proportions, as factor ratios change. On the other hand, returns to scale operate in the long run where all factors are variable and scale increases proportionally.
In simple words: Return to a factor is about changing one input while keeping others fixed. Returns to scale is about changing all inputs at the exact same rate.

Exam Tip: Mention that the factor ratio remains constant in returns to scale but changes in return to a factor.

Question 39. Explain the three laws of return to scale.
Answer: The three laws of returns to scale are:
1. **Increasing Returns to Scale (IRS):** Occurs when the percentage increase in output is greater than the percentage increase in all inputs.
2. **Constant Returns to Scale (CRS):** Occurs when the percentage increase in output is exactly equal to the percentage increase in all inputs.
3. **Diminishing Returns to Scale (DRS):** Occurs when the percentage increase in output is less than the percentage increase in all inputs.
In simple words: If you double your inputs: getting more than double the output is increasing returns; getting exactly double is constant returns; getting less than double is diminishing returns.

Exam Tip: Clearly define the input-output percentage relationship for each of the three stages.

Question 40. What factors lead to Diseconomies, which cause Diminishing returns to scale?
Answer: Diminishing returns to scale are caused by internal and external diseconomies of scale, such as communication gaps, management and coordination difficulties in large organizations, and rising input costs due to increased industry-wide demand.
In simple words: As a business gets too huge, it becomes harder for managers to talk to each other, decisions take longer, and raw materials can get more expensive.

Exam Tip: Categorize these into "internal" (management issues) and "external" (high prices of crowded input markets) diseconomies.

Question 41. Name two factors behind increasing return to scale.
Answer: Two major factors behind increasing returns to scale are the specialization and division of labor, and the indivisibility of large-scale machinery.
In simple words: Growing bigger lets workers focus on doing one job very well, and allows the company to use highly efficient heavy machinery that only makes sense for large operations.

Exam Tip: Use terms like "internal economies of scale" and "division of labor" as these are key marking terms.

Question 42. How Specialization and division of labor lead to increasing return to scale?
Answer: When scale increases, a firm can split work into smaller, repetitive tasks. This specialization and division of labor allows workers to become highly skilled and fast at their specific roles, reducing wasted time and dramatically boosting productivity per worker.
In simple words: When you grow, workers don't have to keep switching tasks. By focusing on one simple job, they work faster and make fewer mistakes, which increases overall output.

Exam Tip: Explain how this process reduces idle time and raises overall labor productivity.

Question 43. Complete the following table: -
Answer:

*Working Notes:*
- For Unit 1: \( AP = \frac{TP}{1} = 20 \), \( MP = TP_1 - TP_0 = 20 \).
- For Unit 2: We are given \( AP = 21 \) and \( MP = 22 \). Thus, \( TP_2 = 2 \times 21 = 42 \). (This is consistent as \( TP_2 - TP_1 = 42 - 20 = 22 = MP_2 \)).
- For Unit 3: Given \( TP = 66 \). Thus, \( AP = \frac{66}{3} = 22 \) and \( MP = TP_3 - TP_2 = 66 - 42 = 24 \).
- For Unit 4: Given \( AP = 22 \) and \( MP = 22 \). Thus, \( TP_4 = TP_3 + MP_4 = 66 + 22 = 88 \). (This matches \( TP_4 / 4 = 88 / 4 = 22 = AP_4 \)).
- For Unit 5: Given \( AP = 21 \). Thus, \( TP_5 = 5 \times 21 = 105 \). Then \( MP_5 = TP_5 - TP_4 = 105 - 88 = 17 \).
In simple words: By using the formulas for average product (\( TP / L \)) and marginal product (\( TP_n - TP_{n-1} \)), we can fill in all the missing numbers in the table step-by-step.
Exam Tip: Double check your calculations by verifying that the sum of the marginal products matches the final total product.

Question 44. Two inputs Labour (L) and Capital (K) are used in Producing a product. Identify the various returns to scale From the following schedule. Give reasons also.

Answer: We can identify the returns to scale by comparing the percentage change in inputs with the percentage change in total output:
1. **From (1K + 1L) to (2K + 2L):** Inputs are doubled (100% increase). Output increases from 100 to 240, which is a 140% increase. Since the percentage increase in output (140%) is greater than the percentage increase in inputs (100%), this represents **Increasing Returns to Scale**.
2. **From (2K + 2L) to (3K + 3L):** Inputs increase by 50%. Output increases from 240 to 360, which is also a 50% increase. Since the percentage increase in output is exactly equal to the percentage increase in inputs, this represents **Constant Returns to Scale**.
3. **From (3K + 3L) to (4K + 4L):** Inputs increase by 33.33%. Output increases from 360 to 450, which is a 25% increase. Since the percentage increase in output is less than the percentage increase in inputs, this represents **Diminishing Returns to Scale**.
In simple words: First, doubling our inputs more than doubles our output (increasing returns). Next, adding 50% more inputs gives exactly 50% more output (constant returns). Finally, adding more inputs leads to a smaller percentage gain in output (diminishing returns).
Exam Tip: Show the percentage calculations for both inputs and outputs to support your reasons for each stage.