3. a local charity sponsors a 5k race to raise money. it receives $55 per race entry and $10,000 in donations, but it must spend $15 per race entry to cover the cost of the race. write and solve an inequality to determine the number of race entries the charity needs to raise at least $55,000.

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.