I don't think you'll be receiving any requests for tutoring anytime soon...maybe 2-3 months from now.
However, to test your knowledge, here's a quick brain exercise.
When you add Sally and Kerry's ages together, the sum is 44 years. Now Sally is twice as old as Kerry was when Sally was half as old as Kerry will be when Kerry is three times as old as Sally was when Sally was three times as old as Kerry. With that information, figure out Sally's age.
Have fun, and good luck!