This topic would deal with problems on subtraction of decimal fractions. We have already learnt how to perform subtraction on decimal fractions. In order to perform subtraction on decimal fraction we need to first change the set of decimal numbers into like decimals and then arrange them in proper columns with greater number in the first row and smaller number in the second row and the decimal point in one vertical line. Then the subtraction is performed ignoring the decimal point and the end after the result is obtained the decimal point is placed in proper location. Here learners need to do this subtraction in problem sums or story sums as the problem would be given in a story form and the learners need to understand what they are required to do.
Here are few examples on problems on subtraction of decimal fractions:
1. There was
100.65 liters of water in a tank. Due to leakage 15.85 liters of water is being
wasted. Find the remaining water in the tank.
9 9 16
Liters of water in the
0 0 . 6 5
Liters of water wasted due to leakage = _ 1 5 . 8 5
Liters of water remaining in the tank = 8 4 . 8 0
Here there is 100.65 litres of water in the tank and 15.85 litres of water has wasted due to leakage. In order to find out the remaining water in the tank we need to subtract 15.85 litres from 100.65 litres.
2. Weight of Inez
at the age of 2 years was 12.05 kg and now after 1 month due to fever doctors
told that her weight reduced by 1.5 kg. Find her present weight.
Here first we need to change the decimals into like decimals i.e. 12.05 kg and 1.50 kg (by adding zero at the end)
Weight of Inez at 2
years of age = 1
2 . 0 5 kg
Weight reduced due to fever = - 1 . 5 0 kg
Present weight of Inez = 1 0 . 5 5 kg
Here the weight of Inez at 2 years is given as 12.05 kg and her weight have reduced by 1.5 kg during 1 month due to fever. In order to find out her present age after fever we need to subtract her reduced weight (i. e. 1.5 kg) from her original weight that is 12.05 kg.
3. Alice purchased books price $ 4.50 but she has paid only $2.30 as she was in short of money. Find the amount remaining to be paid by Alice.
Price of books purchased by Alice = $ 4 . 5 0
Price of books paid by Alice = $ 2 . 3 0
Amount of money remaining to be paid = $ 2 . 2 0
Here the price of books is $ 4.50 but due to shortage of money only $ 2.30 could be paid. Alice needs to pay the remaining amount. For finding the remaining amount we need to subtract the amount paid by Alice (i.e. $ 2.30) from the price of the book (i.e. $ 4.50).