Question 844233
Let's say Charlie is c, Diane is d, Paco is p, and Brett is b. Now plug what you know for each value: c=b+15; d=46; p=d-10; p=b+33.
First solve for Paco's age (p=d-10), where d=46: (p=46-10) = p=36.
Now use Paco's age to solve for Brett's age (p=b+33), where p=36
(36=b+33) = b=3.
Now use Brett's age to find Charlie's age: (c=b+15), where b=3
(c=3+15) = c=18
Charlie is 18 years old.