Question

The present ages of a and b are in the ratio 6;4 five years ago their ages were in the ratio 5:3 find their present age?

Answer 1

Answer:

Let the present ages of a and b be in the ratio 6x : 4x

Before 5 years their ages would have been 6x - 5 and 4x - 5. This was in the ratio 5 : 3.

=> 6x - 5 : 4x - 5 :: 5 : 3

Product of Means = Product of Extremes

=> ( 6x - 5 ) ( 3 ) = ( 4x - 5 ) ( 5 )

=> 18x - 15 = 20x - 25

=> 25 - 15 = 20x - 18x

=> 10 = 2x

=> x = 10 / 2 = 5

Hence their present ages are:

a = 6x = 6 * 5 = 30 years

b = 4x = 4 * 5 = 20 years