Stan’s Skate Shop is having a sale on skateboards. The original price for its Extreme Skateboard was $84.50. The sale price for the skateboard is $50.70. What is the percent decrease in the price of the skateboard?

Suppose that 3% of all athletes are using the endurance-enhancing hormone epo (you should be able to simply compute the percentage of all athletes that are not using epo). for our purposes, a “positive” test result is one that indicates presence of epo in an athlete’s bloodstream. the probability of a positive result, given the presence of epo is .99. the probability of a negative result, when epo is not present, is .90. what is the probability that a randomly selected athlete tests positive for epo? 0.0297