A video store offers two yearly pricing plans: A. $10.00 charge plus $2.50 for each movie rented. B. $4.00 charge (total) for the first 4 movies rented plus $3.00 per movie. How many movies will a person need to rent in order to spend an equal amount of money using either plan?

  36

Step-by-step explanation:

The cost of renting n movies using Plan A is ...

  c = 10 +2.50n

The cost of renting n movies using Plan B is ...

  c = 4 +3(n -4) . . . . for n ≥ 4

The two costs are equal when ...

  4 +3(n -4) = 10 +2.50n

  0.50n = 18 . . . . . . . . . . add 8 -2.50n and simplify

  n = 36 . . . . . . . . . . multiply by 2

A person would have to rent 36 movies to spend the same using either plan.