Question

A's present age is to B's present age is 7:9. twelve years ago, their ages were in ratio 3:5 when would the ratio of their ages be 6:7​

Answer 1

Answer:

After 15 years

Step-by-step explanation:

A:B = 7:9, let there age be 7x and 9x.

12 years ago there age was 7x-12 and 9x-12.

As given in the question

(7x-12)/ (9x-12) = 3/5

or 5(7x-12) = 3(9x-12)

or 35x -60 = 27x - 36

35x-27x = -36+60

8x = 24

X = 3

so there ages are 7×3 and 9×3 i.e 21 and 27 years.

let after Y years their ages are in the ratio 6:7

(21+ Y)/(27+Y) = 6/7

or 7(21+Y) = 6(27+Y)

147+7Y = 162+6Y

Y = 15 years