Delbert is choosing between two membership options at the local movie society. A Director membership costs $250 per year, and it costs $3.75 each time Delbert sees a movie. A Producer membership costs $325 per year, and it costs $2.50 each time Delbert sees a movie.

a) How many movies would Delbert have to see in one year for the two options to cost the same amount?

b) If Delbert plans to see 100 movies in a year, which membership would be the least expensive?

Write a system of equations that can be used to solve the problem. Then solve the system and determine the answer.