An engineer is going to redesign an ejection seat for an airplane. The seat was designed for pilots weighing between

140

lb and

191

lb. The new population of pilots has normally distributed weights with a mean of

149 lb

and a standard deviation of

29.9 lb

.

a. If a pilot is randomly selected, find the probability that his weight is between

140

lb and

191

lb.

The probability is approximately

nothing

.

(Round to four decimal places as needed.)

b. If

37

different pilots are randomly selected, find the probability that their mean weight is between

140

lb and

191

lb.

The probability is approximately

nothing

.

(Round to four decimal places as needed.)

c. When redesigning the ejection seat, which probability is more relevant?

A.

Part (a) because the seat performance for a sample of pilots is more important.

B.

Part (b) because the seat performance for a sample of pilots is more important.

C.

Part (a) because the seat performance for a single pilot is more important.

D.

Part (b) because the seat performance for a single pilot is more important.