Carlos is 8 years older than Maria. 4 years ago maria was two thirds as old as Carols. How old are they?

1 Answer
Jul 7, 2016

Maria is 28 and Carlos is 36.

Explanation:

I call the age of Carlos today C and the one of Maria M.

The first relationship is

C=8+M

the second relationship is that

M-4=2/3C.

I substitute the first in the second

M-4=2/3*(8+M)

M-4=16/3+2/3M

multiplying by 3 both sides

3M-12=16+2M

M=16+12

M=28

and C is

C=8+28=36.

Just to verify, Carlos is 8 years older of Maria (he is 36 and Maria is 28) and four years ago Maria was 24 that is two third of the age of Carlos.