Question

Six years ago, ravi's age and his father's age were in the ratio 2 : 5. six years hence ravi's father’s age will be twice of ravi's age. what is the present age of ravi's father?

Answer 1

let ,
ravi's age be 2x
his father age be 5x
after six years
ravi's age will be 2x+6
his afther age will be 5x+6
given  
 ravi's father’s age will be twice of ravi's age
so,
2(2x+6)=5x+6
4x+12=5x+6
12-6=5x-4x
x=6
so, the present age of ravi is 12 years
and his father's age is 30 years