Question

Ace's grandfather is 3 years older than Aces grandmother. Their combined age is 121 years. How old is each?

Answer 1

f=m+3
f+m=121

solve this sytem of equations:
as f=m+3 we can substitute this instead of f into second equation:

m+3+m=121
m=59 grandmother is 59
grandfather is f=m+3=59+3=62
62+59=121

grandfather is 62
grandmother is 59