Catalina buys food and medicine for the dogs at a pet store. She spends 4 times as much on food as she spends on medicine. She spends a total of $400. How much did Catalina spend on food and on medicine? Let x represent the amount spent on food. Let y represent the amount spent on medication.

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.