Question 485939
son x years
john 5x years

3 years ago their ages were 
son x-3
John 5x-3

5x-3 = x-3+24
5x-3=x+21
5x= 21+3 +x
5x-x= 24
4x=24
x= 24/4 
x= 6 Son's age now.
John's age = 6*5 =30 years