The Chorus at Eastside High School is holding a fund-raiser. The goal is to raise $500. The graph shows the number of short sleeve and long sleeve t-shirts the chorus needs to sell in order to raise $500.

If they sold only short sleeve t-shirts and raised exactly $500, how many shirts did they sell?
A) 15
B) 20
C) 25
D) 50

Saline iv fluid bags cost $64.20 for 24, 1000 ml bags from one supplier. a new supplier sells 500 ml bags for $2 each. the hospital uses about 10,000, 1000 ml bags each month. nurses report that about half of the bags are more than half full when they are discarded. if you are going to use only one supplier, which size bag provides the best deal, and how much will you save each month? compare the cost of the new supplier to the current one.

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

How do you determine if an ordered pair is a solution to a given equation?