One faucet fills a sink in 4 minutes. A drain at the bottom of the sink can empty the sink in 5 minutes. If the faucet is turned on and the drain is open, how many minutes will it take to fill the
sink? Enter ONLY the number.

Twenty-five percent of the customers entering a grocery store between 5 p.m. and 7 p.m. use an express checkout. consider five randomly selected customers, and let x denote the number among the five who use the express checkout.

Trish receives $450 on the first of each month. josh receives $450 on the last day of each month. both trish and josh will receive payments for next four years. at a discount rate of 9.5 percent, what is the difference in the present value of these two sets of payments?

Teams of 4 are competing in a 1/4 mile relay race. each runner must run the same exact distance. what is the distance each teammate runs?