Richard and Teo have a combined age of 36. Richard is 15 years older than twice Teo's age. How old are Richard and Teo?

21 a stick 7 inches long is broken into two pieces, so that one piece is twice as long as the other one. how long are the two pieces?

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50.

7+(3n++8) what is the answer to this?