Page 11 - ICSE Math 5

Number
1 Numberss

Learning Outcomes

Students will be able to learn:
 numbers up to crores (9-digit numbers).
 Indian and International number systems.
 the place value and face value of numbers.
 the expanded and standard form of numbers.
 to compare large numbers.
 to arrange numbers in ascending and descending orders.
 to form the smallest and the largest numbers using the given digits.
 to round off numbers to the nearest 10, 100 and 1,000.

Numbers up to Crores

We have already learnt about 6-digit numbers in the previous class. Now let’s learn about
numbers which are larger than 6-digit numbers.

We already know that 1,00,000 is the smallest 6-digit number and 9,99,999 is the largest 6-digit
number. Now observe the following pattern carefully.

On adding 1 to the largest 6-digit number, we obtain the smallest 7-digit number.

1 + 9,99,999 = 10,00,000 It is read as ten lakhs.

The largest 7-digit number is 99,99,999. It is read as ninety-nine lakh ninety-nine thousand nine
hundred ninety-nine.

Similarly, when we add 1 to the largest 7-digit number, we obtain the smallest 8-digit number.

1 + 99,99,999 = 1,00,00,000 It is read as one crore.
The largest 8-digit number is 9,99,99,999. It is read as nine crore ninety-nine lakh ninety-nine
thousand nine hundred ninety-nine.

In the same way, when 1 is added to the largest 8-digit number, we obtain the smallest 9-digit
number.
1 + 9,99,99,999 = 10,00,00,000 It is read as ten crores.

The crores period comes after the lakhs period and consists of crores and ten crores.

10,00,00,000 is the smallest 9-digit number while 99,99,99,999 is the largest 9-digit number.

The largest 9-digit number, 99,99,99,999 is read as ninety-nine crore ninety-nine lakh ninety-nine
thousand nine hundred ninety-nine.

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