Age of Rahul's father is 3 times Rahul's age now.After 15 years he will be twice the age of Rahul. Find their present age.

Answer 1

Getting late...let's see if we set this up correctly:
3R=F
F = 2R + 15 (I'm not quite sure about this sentence, but substitute and solve for one of the unknowns.)

I chose F:
3R = 2R + 15
R = 15
Substitute the value of R into one of the sentences and find F. 3R = 45 = F. Check in the other sentence. F = 2(15) + 15 = 45. Works. ( If I wrote the second sentence correctly.)

Answer 2

13

Answer 3

Rahul's father's age = -36