Question 1160803
<pre>
J = James' age
Y = Joy's age

J = 3Y             (1)  from "James is 3 times as old as Joy."
J-3 = 4(Y-3)       (2)  from "Three years ago, he was four times as old as Joy."

Substitute 3Y from (1) for J in (2):
3Y-3 = 4(Y-3)
3Y-3 = 4Y-12
  Y = 9  ==>  J = 27


Ans: Joy is 9, James is 27

Check:  James should be 3*Joy's age:  27 = 3*9  (ok)
    and three years ago he should have been 4*Joy's age:  27-3 = 24,  which is 4*6,  and Joy was 9-3=6  (ok)