Richard is 6 years older than Lisa, and in 5 years the sum of their ages will be twice as much as the sum of their ages 4 years ago. Find their present ages.

If we assume that Lisa is x years old, then Richard will be (x + 6) years

In 5 years time

Lisa = x + 5 years

Richard = x + 11 years

sum will be 2x + 16 years

4 years ago

Lisa = x-4 years

Richard = x + 2

Sum will be 2x - 2

Therefore;

2 (2x-2) = 2x + 16

4x - 4 = 2x + 16

2x = 20

x = 10

Thus, the present age of Lisa is 10 years and that of Richard is 16 years