The ratio of present ages of Hema and Chinnu is 13:17. Four years ago the ratio of their ages was 11:15. What will be the ratio of their ages six years hence ?

A 3 : 7

B 7 : 9

C 4 : 5

D 1 : 3

Correct Answer: Option C

Let ,

their present ages be 13x and 17x.

ACQ ,
13x-4/17x-4 = 11/15.

or, 15(13x-4) = 11(17x-4)

or, 195x - 60 = 187x -44

or , 8x = 16
so , x = 2

after 6 years,

Hema's age will be - 13*2+6= 32

Chinnu's age will be - 17*2 + 6 = 40

so their age's ratio = 32/40 = 4/5