Elle has a sticker book with 12 pages of stickers. Her friend Erin's book has 3 times more pages. How many pages are in Erin's book?

Find the area of a trapezoid with a height of 23, base 1 of 10 and base 2 of 18

One card is dealt from a 52 card deck. find the probability that the dealt card is a 4 or a black 7

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.