Page 68 - Ganit Kaushal

Ex 2. Insert commas in 754321 and write it in words according to the International system.
Sol. 754,321; “Seven hundred fifty-four thousand three hundred twenty-one”.

Ex 3. Write “Twenty million and eight” in numerals.
Sol. 20,000,008
Ex 4. Write “Eight million five hundred seventeen thousand seven hundred fifteen” in numerals.
Sol. 8,517,715
Ex 5. Write the following number in words: 718,456,329.
Sol. Seven hundred eighteen million four hundred fifty-six thousand three hundred twenty-nine.

Ex 6. How many millions make one billion?
Sol. Since 1 billion = 1000 million. So, 1000 millions make one billion.
3.4 FORMING GREATEST AND SMALLEST NUMBERS

With the given digits, we can form the greatest and smallest numbers using the following rules:
(i) For the greatest number, write the digits in decreasing order, i.e., starting with the greatest digit
from the extreme left.
(ii) For the smallest number, write the digits in increasing order, i.e., starting with the smallest non-
zero digit from the extreme left.
(iii) If zero is among the digits, place it in the second left position, and then write the remaining digits
in increasing order to form the smallest number.
Ex 1. Write the greatest and smallest 5-digit numbers using 3, 4, 9, 0, and 8.

Sol. The greatest 5-digit number using the given digits is 98430 and the smallest 5-digit number using the
given digits is 30489.

Ex 2. Write the greatest 6-digit number using the digits 8, 7, 0, 6, 9, L TTh Th H T O
and 2 with 9 at the hundreds place. 9
Sol. First, we fix 9 in the hundreds place. Then arrange the remaining
digits in descending order at the empty places. L TTh Th H T O
So, the required 6-digit number is 876920. 8 7 6 9 2 0

n-digit Greatest and Smallest Number

We know that 1 is the smallest one-digit number and 9 is the greatest one-digit number. Look at the following
pattern. It will help you to understand largest and smallest numbers.
Largest one-digit number = 9
Smallest two-digit number = 10, that is (9 + 1 = 10) Remember
Largest two-digit number = 99 The largest number of a particular
Smallest three-digit number = 100, that is (99 + 1 = 100) no. of digits contains all 9s and the
Largest three-digit number = 999 smallest contains 1 at the highest
Smallest four-digit number = 1000, that is (999 + 1 = 1000) place with all the rest being 0s.
This pattern continues for larger numbers.
Continuing the pattern, 999999 is the greatest 6-digit number, and 999999 + 1 = 1000000 is the smallest 7-digit
number, and this can continue forever. Therefore, we conclude that:

Largest n-digit number + 1 = smallest (n + 1)-digit number

66 Mathematics-6