9. Jennifer is now 3 years older than Peter. If, in 12 years, the sum of their ages will be 61, how
old is Jennifer now?

Relax

Respuesta :

Answer:

  20

Step-by-step explanation:

In 12 years, the sum of their ages will be 24 more than it is now. The sum of their ages now is 61-24 = 37.

If Jennifer is 3 years older than Peter, we have ...

  j + (j -3) = 37

  2j = 40 . . . . . . add 3

  j = 20 . . . . . . . divide by 2

Jennifer is now 20 years old.

_____

Peter is now 17 years old. In 12 years, they will be 29 and 32, so their ages will sum to 61.