How old are two boys?

Question

Bob is twice as old as Steve. 3 years ago the sum of their ages was 45. How old are they today?

Answer 1

Elizabeth,

 

Let Steve's age be S years

Bob's age = 2*S

 

3 years ago their ages were s-3 and 2s-3

 

Sum of their ages 3 yrs ago = s-3 + 2s -3 = 45

3s -6 = 45

3s = 51

s = 17

 

So now Steve's age is 17 and Bob's age is 17*2 = 34 years