Mary has had five unit tests in math so far this semester.
she has achieved scores of 86, 82, 93, 88, and 89 out of 100.
she knows there are only two unit tests left, and would like to achieve an overall average of 90 on the seven tests.
a) can she achieve her desired average? if so, what average would she need to achieve on the last two tests?
b) what is the minimum score she could get on either of the last two tests, and still achieve an overall average of 90?

Write the pair of fractions as a pair of fractions with a common denominator

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

Ascientist has discovered an organism that produces five offspring exactly one hour after its own birth, and then goes on to live for one week without producing any additional offspring. each replicated organism also replicates at the same rate. at hour one, there is one organism. at hour two, there are five more organisms. how many total organisms are there at hour seven? 2,801 19,531 19,607 97.655