Question

Mary is x years old. How old will she be in 12 years? How old was she 2 years ago?

Answer 1

As Mary isn't given an age, you must use algebra:

"How old will she be in 12 years?"
So this is 12 more years than her age. If her age is x:
x + 12

"How old was she two years ago?"
This is 2 years less than her age. If her age is x:
x - 2