SOLUTION:

Question 262974:
Answer by ajmisra(4) (Show Source): You can put this solution on YOUR website!
The best way to go go about is to form and equation with one variable 'x'
Lets say: Evan's current age is 'x'
Then Cody, being twice as old as Evan is '2x'
Three years back there ages were: 'x-3'(Evan)and '2x-3'(Cody)
Also three years back their sum of ages was 27; thus:
(x-3)+ (2x-3)= 27
i.e. x - 3 + 2x - 3 = 27
i.e. 3x - 6 = 27
i.e. 3x - 6 + 6 = 27 + 6 (adding 6 to both sides of the equation)
i.e. 3x = 33
i.e. 3x/3 = 33/3 (dividing both sides by 3)
i.e. x = 11
Thus Evan's ages is 11 and Cody being twice Evan's age is 22.
(You can verify three years back: Evan was 8 and Cody was 19; and the sum of their ages was 27)