The mother is 21 years older than the child.
6 years from now, the mother will be 5 times as old as the child.
Question : Where is the father?
Answer
The mom is 21 years older than the child, so…
M = C + 21
In 6 years from now the mom will be 5 times as old as the child.
M + 6 = (C + 6) * 5
(C + 21)+ 6 = (C + 6) * 5
C + 27 = 5C + 30
-3 = 4C
C = -3/4
The child is -3/4 years old, i.e. it’ll be born in 9 months’ time.
So, the father is probably near by.