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34212 4994
Solution:(a) = 5702 (b) = 454
6 11
Here, decimal is placed after 2 digits Here, decimal is placed after 2 digits
from the right side in the number from the right side in the number
342.12. So, we put decimal point 49.94. So, we put decimal point after
after 2 places from the right in the 2 places from the right in the quotient
quotient obtained. obtained.

Thus, 342.12 ÷ 6 = 57.02 Thus, 49.94 ÷ 11 =4.54
Division of a Decimal Number by Another Decimal Number

Convert both the divisor and dividend into whole numbers by multiplying them by the same
number (such as 10, 100, 1000 etc.).
Then,divide the new dividend by the whole number.

Example 18: Divide: 3.45 ÷ 1.5
.
.
345 345 100 345
×
Solution: = = = 23
.
15 15 100 150
.
×
.
\ 3.45 ÷ 1.5 = 2.3
Division of a Decimal by 10, 100, 1000, etc.
When dividing a decimal number by 10, 100, 1000, etc,. The digits of the quotient remains same
as the digit of the decimal number. Move the decimal point as many places to the left as there are
zeros in the divisor.
Example 19: Divide the following decimal numbers:

(a) 29.83 by 10 (b) 358.94 by 100 (c) 757.14 by 1000
Solution: We have,

(a) 29.83 ÷ 10 = 2.983 [Shifting 1 place to left]
(b) 358.94 ÷ 100 = 3.5894 [Shifting 2 places to left]
(c) 757.14 ÷ 1000 = 0.75714 [Shifting 3 places to left]

Practice Time 2F

1. Divide the following:
(a) 36.24 ÷ 12 (b) 66.5 ÷ 7 (c) 2.9 ÷ 58 (d) 74.64 ÷ 24
2. Divide the following:
(a) 8.432 ÷ 1.36 (b) 0.052 ÷ 1.3 (c) 1.064 ÷ 0.4 (d) 12.45 ÷ 1.5
3. Divide the following:
(a) 4.96 ÷ 10 (b) 3.6 ÷ 1000 (c) 1.485 ÷ 100 (d) 92.782 ÷ 1000
4. The product of two decimals is 345.45. If one number is 14.7, find the other.
5. The total cost of 25 perfume bottles is `3719; find the cost of each perfume bottle.
6. A boy bought 6 dozen bananas for `302.50. Find the cost of 1 banana.

7. A tin holds 22.8 litres of juice. How many such tins will be required to hold 775.2 litres of juice?
8. A vehicle covers a distance of 68.4 km in 3.6 litres of petrol. How much distance will it cover in 1
litre of petrol?

47 Fractions and Decimals