1. Given below are data on the diameters of steel ball bearings from a particular production process.
1.72 1.62 1.69 0.79 1.79 0.77
(a) Construct a normal probability plot for these values. What do you conclude?
(b) Construct a 70% prediction interval for the diameter of a new randomly chosen ball bearing.
2. A particular population is known to have an exponential distribution with mean of 5.
(a) If 40 items are selected at random from this population, what is the probability that their average will exceed 5.5?
(b) If one item is selected at random from this population, what is the probability that its value will exceed 5.5?