Question: A product coming off an assembly line has been found to weigh on average 17 pounds, with a standard deviation of 1.8. Thirty samples are chosen at random from the line.
(a) What is the probability that these samples will weigh on average between 16.8 and 17.2 pounds?
(b) What is the probability that they weigh on average at least 16.7 pounds?
(c) Find the probability that they do not weigh on average less than 17.2 pounds.