Question 509824
Let x = your age now
then
(x+25) = Mom's age
and
(x+27) = Dad's age
:
The sum
x + (x+25) + (x+27) = 91
3x + 52 = 91
3x = 91 - 52
3x = 39
x = 39/3
x = 13 yrs is your present age
:
:
Check this; find the sum of all the ages:
 13 + (13+25) + (13+27) = 
 13 + 38 + 40 = 91