CBSE Class 6 Mathematics Knowing our Numbers Assignment Set 05

Important Concepts

Indian System of Numeration: Commonly used values in table

International System of Numeration: Commonly used values in table

Question. Write the numbers in according to Indian or international system of numeration in words
a) 19,15,60,050
b) 20,48,74,873
c) 97,97,97,997
d) 507,476,123
e) 100,005,567
Answer:
a) Nineteen crore, fifteen lakh, sixty thousand, fifty.
b) Twenty crore, forty-eight lakh, seventy-four thousand, eight hundred seventy-three.
c) Ninety-seven crore, ninety-seven lakh, ninety-seven thousand, nine hundred ninety-seven.
d) Five hundred seven million, four hundred seventy-six thousand, one hundred twenty-three.
e) One hundred million, five thousand, five hundred sixty-seven.
In simple words: Commas help us read large numbers. In the Indian system, commas go after three digits, and then after every two digits. In the International system, commas go after every three digits.

Exam Tip: Check the commas first. This helps you know if the number is in the Indian or International system.

Question. Write the numbers in according to Indian or international system of numeration in numerals
a) Five crores,five lakhs,five thousands
b) Fifty six crores,nineteen lakh,eight thousand and fifteen
c) One hundred ten million,two hundred thousand and three hundred forty eight
d) Two hundred thirty four million,eighteen thousand and three hundred forty eight
e) One million,one thousand and one
f) One crore,one lakh,one thousand,one hundred and one
Answer:
a) 5,05,05,000
b) 56,19,08,015
c) 110,200,348
d) 234,018,348
e) 1,001,001
f) 1,01,01,101
In simple words: When you write numbers, use zeros for any places that are left out.

Exam Tip: Read the full number name first. Look for skipped places like lakhs or thousands and fill them with zeros.

Question. Write each of the following in the Expanded notation form
a) 8,40,32,167
b) 90,909,090
c) 17,865,432
d) 6,05,43,091
e) 10,00,976
Answer:
a) \( 8,00,00,000 + 40,00,000 + 30,000 + 2,000 + 100 + 60 + 7 \)
b) \( 9,00,00,000 + 9,00,000 + 9,000 + 90 \)
c) \( 1,00,00,000 + 70,00,000 + 8,00,000 + 60,000 + 5,000 + 400 + 30 + 2 \)
d) \( 6,00,00,000 + 5,00,000 + 40,000 + 3,000 + 90 + 1 \)
e) \( 10,00,000 + 900 + 70 + 6 \)
In simple words: We write each digit based on its value. Then we put plus signs between them.

Exam Tip: Do not forget any zeros that hold a place. But you do not need to write "+ 0" in the final sum.

Question. Write the Expanded notation form in numerals for the following
a) 1,00,00,000+70,00,000+6,00,000+40,000+3,000+800+20+5
b) 4×10,00,000+6×100,000+3×10,000+7×1000+1×100+7×10
c) 90,00,000+40,00,000+3000+20+6
d) 8×10,00,000+6×1000+3×10+1
Answer:
a) 1,76,43,825
b) 46,37,170
c) 90,43,026
d) 80,06,031
In simple words: Add all the values together to find the final number. Put a zero if a place value is empty.

Exam Tip: Write down place value columns like Hundreds and Tens. Fill them in to avoid mistakes.

Question. How many numbers exist between 51 and 100?
Answer: There are 48 numbers that exist strictly between 51 and 100.
In simple words: We do not count 51 and 100. We only count from 52 to 99. This gives us 48 numbers.

Exam Tip: To find numbers between two values, subtract them and then subtract 1. For example, \( 100 - 51 - 1 = 48 \).

Question. How many thousands make a million?
Answer: 1,000 thousands make a million.
In simple words: It takes one thousand groups of one thousand to equal one million.

Exam Tip: Write 1,000,000 (million) and divide it by 1,000 (thousand) to find the answer quickly.

Question. How many millions make a billion?
Answer: 1,000 millions make a billion.
In simple words: You need one thousand millions to equal one billion.

Exam Tip: In the International system, each new group is 1,000 times bigger than the last one.

Question. How many lakhs make a million
Answer: 10 lakhs make a million.
In simple words: Ten lakhs are equal to one million in the International system.

Exam Tip: Write 1,000,000 (one million) with Indian style commas as 10,00,000 to see that it represents 10 lakhs.

Question. How many millions make ten crores?
Answer: 100 millions make ten crores.
In simple words: Ten crores is equal to one hundred million.

Exam Tip: Use the conversion that 1 crore = 10 million. Therefore, 10 crores = 100 million.

Question. Fill in the gap:
a. 1 crore=_____lakhs
b. 1 Millions=______thousands
c. 10 crores=_______millions
d. 1 Hundred thousand=______lakhs
Answer:
a. 1 crore = 100 lakhs
b. 1 Millions = 1,000 thousands
c. 10 crores = 100 millions
d. 1 Hundred thousand = 1 lakhs
In simple words: Fill in the numbers that make both sides equal in value.

Exam Tip: To verify your answers, write out each number in digits on both sides to check if they match.