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Number Number name

Forty-six billion seven hundred thirty-eight million one hundred ninety
46,738,190,325
thousand three hundred twenty-five
Six billion four hundred ninety-four million three hundred eighty-three
6,494,383,501
thousand five hundred one

Use of Commas in Writing Large Numbers
• In Indian system of numeration, commas are used to mark thousands, lakhs and crores. The first
comma is used after hundreds place, i.e., three places from the right, which marks thousands.
The second comma is used two digits later, i.e., five digits from the right, which marks lakhs
and the third comma is used further two digits later, i.e., seven digits from the right, which
marks crores.
• In International system of numeration, commas are used to mark thousands, millions and
billions. The first comma marks thousands, second marks millions and third marks billions,
etc. It means the first comma is used three places from the right, the second comma is used
three digits later, i.e., six digits from the right and finally the third comma is used further three
digits later, i.e., nine digits from the right.

• While writing the number names, we do not use commas.
Example 2: Fill in the blanks:

(a) 1 lakh = _________ thousand (b) 1 crore = _________ million
(c) 1 million = _________ lakh (d) 1 million = _______ hundred thousand
Solution: (a) 100 (b) 10 (c) 10 (d) 10

Example 3: Write the numerals for the following with commas at correct places.
(a) Seventy-two lakh thirty-five thousand four hundred eight

(b) Eight crore ninety-four lakh five hundred two
(c) Seventeen million three thousand four

(d) Twenty-nine billion one hundred seventy-one million four hundred two thousand
three hundred seventy-two
Solution: (a) 72,35,408 (b) 8,94,00,502 (c) 17,003,004 (d) 29,171,402,372

Example 4: Insert commas suitably and write the number names according to Indian system of
numeration:
(a) 87595762 (b) 7013121 (c) 63432701
Solution: Number Number with commas Number name

(a) 87595762 8,75,95,762 Eight crore seventy-five lakh ninety-five
thousand seven hundred sixty-two

(b) 7013121 70,13,121 Seventy lakh thirteen thousand one
hundred twenty-one
Six crore thirty-four lakh thirty-two thousand
(c) 63432701 6,34,32,701
seven hundred one

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