The income of A, B and C are in the ratio 1 : 2 : 3 and their spending’s are in the ratio 4 : 7 : 13. If A saves 20% of his income, then find the ratio of their savings.

1 : 3 : 2

               A    :    B    :    C

Income:   1    :    2    :    3   ..........(i)

Exp.:       4    :     7    :   13    .........(ii)

**Note: If a saves 20% = \(\frac{1}{5}\) of his income, it means 

For A ⇒ Income : Expenditure = 5 : 4.

*[According to this ratio of income and Exp. of A is 1 : 4 but according to condition it should be 5 : 4

Therefor in this situation always follow two steps

a) Make it in the ratio 1 : 1

b) multiply by the new ratio in which we want to convert.]

a)

                     A    :    B    :    C

Income:  4 x (1    :    2    :    3

Exp.:      1 x ( 4    :   7    :    13

b)

                            A    :    B    :    C

Income:   5 x 4 x (1    :    2    :    3

Exp.:       4 x 1 x ( 4    :   7    :    13

New Ratio:

                A     :     B      :    C

Income:   20     :    40     :    60

Exp.:       16     :     28    :     52  

Saving:     4     :     12    :     8

                1     :      3     :     2