There were ships with 3 masts and ships with 4 masts at the Tall ship exhibition. Mollie counted a total of 30 masts on 9 ships she saw. How many of these ships had 4 masts?

33% of college students say they use credit cards because of the rewards program. you randomly select 10 college students and ask each to name the reason he or she uses credit cards. find the probability that the number of college students who say they use credit cards because of the rewards program is (a) exactly two, (b) more than two, and (c) between two and five inclusive. if convenient, use technology to find the probabilities.

The two square pyramids are similar. find the total volume of both pyramids if the ratio of their surface areas is 9/16

If sin(x) = 0 and cos(x) = 1, what is tan(x)?