Question

The ratio of Sunita’s age to Mark’s age is currently 3 to 4, and in 12 years, it will be 5 to 6. What is Mark’s current age?

Answer 1

S/M=3/4 => 4S=3M..............................................(1)
(S+12)/(M+12)=5/6 => 6(S+12)=5(M+12)............(2)
3(1): 12S=9M
2(2): 12S+144=10M+120

2(2)-3(1) =>
144=M+120 => M=24
Solve for S => S=3*M/4=18

Check: S+12=30,  M+12=36   30/36=5/6  ok.

Mark's current age is 24