Paula's age is 4 times Mary's present age. In 6 years time, the sum of their ages will be 57 years. Find their present ages.

Let's make the variable P and M.

4M=P

P+6+6+M=57

Let's put the first equation in as Paula's age.

4M+12+M=57

5M+12=57

5M=45

45:5

9

Mary's present age is 9, so Paula's age is 36.

Let's check the sum of their ages in 6 years.

15+42

57