At the karate school, class a has 8 students with an average age of 6 years. class b has 12 students with an average age of 9 years. the classes combine for a group workout.
what is the average age of the combined classes?

Desmond wants to sell his car that he paid $8,000 for 2 years ago. the car depreciated, or decreased in value, at a constant rate each month over a 2-year period. if x represents the monthly depreciation amount, which expression shows how much desmond can sell his car for today? \ 8,000 + 24x 8,000 - 24x 8,000 + 2x 8,000 - 2x