Question 813490
 James is five years older than his twin sisters who are, a & b
j = a + 5
or
a = j-5
and
j = b + 5
or
b = j-5

The sum of the ages of the twins three years ago is equal to his age five years from now.
(a-3) + (b-3) = j + 5
Replace a and b
(j-5) - 3 = (j-5) - 3 = j + 5
2j - 16 = j + 5
2j - j = 5 + 16
j = 21 yrs is James present age
then the twins are 5 yrs younger
a = 16
b = 16
:
 How old will they be 12years from now?
Add 12 to the above ages