Question 1003232
Call Tom and Tim's age NOW, x and y.
Thus
x + y = 21
In 3 years,
x+3 = 2(y+3) = 2y + 6
and
x = 2y + 3
Now substitute that into the first equation and get
2y + 3 + y = 21
3y = 18
y = 6
x = 15