Question

The income of A, B and C are in the ratio 7:9:12 and their spending are in the ratio 8:9:15.
If A saves ¼th of his income, then the savings of A,B and C are in the ratio of​

Answer 1

Income= Expenditure + Saving

Saving= Income - Expenditure

7x-8y=7x/4

=> 4(7x-8y)=7x

=> 28x-32y=7x

=>28x-7x=32y

=> 21x=32y

=> y=21x/32

A’s Saving = 7x/4

B’s Saving = 9x-9y

=> 9(x-y)

put y= 21x/32

=> 9(x-21x/32)

=> 9(32x-21x/32)

=> 9(11x/32)

=> 99x/32

C’s Saving= 12x-15y

put y=21x/32

=> 12x - 15(21x/32)

=> 12x -315x/32

=> 384x-315x/32

=> 69x/32

Hence the required ratio,

7x/4, 99x/32, 69x/32

56:99:69