Aclub decides to sell t-shirts for $15 as a fundraiser. it cost $20 plus $9 per t-shirt to make the t-shirts. write and solve an equation to find how many t-shirts the club needs to make and sell in order to profit at least $152?
a. 15x - (9x+20) greater than or equal to 150; x greater than or equal to 28.33
b. 15x-9x + 20 greater than or equal to 150; x greater than or equal to 20
c. (8x+20) -15x greater than or equal to 150; x greater than or equal to 20
d. 15x -9 (x+20) greater than or equal to 150; x greater than or equal to 20

Problems and applications q5 four roommates are planning to spend the weekend in their dorm room watching old movies, and they are debating how many to watch. here is their willingness to pay for each film: willingness to pay (dollars) shen antonio dmitri jake first film 10 9 8 3 second film 8 7 6 2 third film 6 5 4 1 fourth film 4 3 2 0 fifth film 2 1 0 0 within the dorm room, the showing of a movie a public good. if it costs $12 to rent a movie, the roommates should rent movies in order to maximize the total surplus. suppose the roommates choose to rent the optimal number of movies you just indicated and then split the cost of renting equally. this means that each roommate will pay $ .