Question

Mrs. Computer is 3 times older than her daughter, Mousy. The sum of their ages is 52. How old is Mousy?

Answer 1

mousy is 13 yrs old

Answer 2

COMPUTER's age = three times MOUSY's age
as an equation can be written as: C = 3 * M

"Sum of their ages" means "when you add their ages together".
COMPUTER's age + MOUSY's age = 52
as an equation that is C + M = 52

So now you have two equations:

C = 3m
C + M = 52

Can you solve it from here?