Subtraction of Decimals
Addition and Subtraction of Decimals : Decimals can be added or subtracted by using the following steps:
Step I Convert the given decimals to like decimals (same decimal places).
Step II Write the decimals in columns with their decimal points directly below each other so that tenths come under tenths, hundredths come under hundredths and so on.
Step III Add or subtract as we add or subtract whole numbers.
Step IV Place the decimal point, in the answer, directly below the other decimal points.

Ex.1     Lata spent M9.50 for buying a pen and M2.50 for one pencil. How much money did she spend?
Sol.: Money spent for pen = M9.50 
        Money spent for pencil = M 2.50
        Total money spent = M9.50 + M2.50
        Total money spent = M12.00

Ex.2     Rahul bought 4 kg 90 g of apples, 2 kg 60 g of grapes and 5 kg 300 g of mangoes. Find the total weight of all the fruits he bought. 
Sol.:  Weight of apples = 4 kg 90 g = 4.090 kg
        Weight of grapes = 2 kg 60 g = 2.060 kg
        Weight of mangoes = 5 kg 300 g = 5.300 kg
        Therefore, the total weight of the fruits bought is 
                            4.090 kg
                            2.060 kg
                          + 5.300 kg
                           11.450 kg
        Total weight of the fruits bought = 11.450 kg.

Ex.3   Amit bought a Maths book for Rs. 45.60 and a geometry box for Rs. 62.55. What is the total amount spent by Amit     ?
Sol.    Money spent on Maths book = Rs. 45.60
          Money spent on Geometry box = Rs. 62.55
     Total amount spent   = Rs. 45.60 + Rs. 62.55 = Rs. 108.15      

Ex.4    An empty box weighs 1 kg 240 g. When filled with oranges it weighs 19 kg 70 g. What is the weight of the oranges ?
Sol.   Weight of empty box = 1 kg 240 g  = 1.240 kg
        Weight of box with oranges  = 19 kg 70 g = 19.070 kg                 
       Weight of oranges = 19.070 kg – 1.240 kg = 17.830 kg.  

Ex.5    A can can hold 12.5 litres of mixed fruit juice. 4.035 litres of apple juice and 6 litres 15 ml of orange juice have been poured in the can. What would be the amount of grape juice that can still be added in the can?
Sol.    Amount of apple juice = 4.035 L
        Amount of orange juice = 6 litres 15 mL = 6.015 L
        Capacity of can = 12.5 L
   Reqd. amount of grape juice   = 12.5 L – (4.035 + 6.015) L                                                       = 12.5 L – 10.050 L = 2.45 L