Two-thirds a number plus 4 is 7

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

50 people men and women were asked if they watched at least one sport on tv. 20 of the people surveyed are women, but only 9 of them watch at least one sport on tv. 16 of the men watch at least one sport on tv. make a a two-way table and a relative frequency table to represent the data.

Out of 50 students surveyed, 16 have a dog. based on these results, predict how many of the 280 students in the school have a dog.