Cathy has obtained a sample mean of 0.8 and sigma^n_i = 1 x^2_i = 25, but she cannot remember if the sample size was 30 or 40. She accidentally erased the data file. How can she figure out the correct sample size?

Ten times the square of a non-zero number is eqaul to ninety times the number

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

Jose is going to use a random number generator 500500 times. each time he uses it, he will get a 1, 2, 3,1,2,3, or 44.