Question

1-

The lengths of pregnancies are normally distributed with a mean of

267267

days and a standard deviation of

1515

days. a. Find the probability of a pregnancy lasting

307307

days or longer. b. If the length of pregnancy is in the lowest

44​%,

then the baby is premature. Find the length that separates premature babies from those who are not premature.Click to view page 1 of the table.

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a. The probability that a pregnancy will last

307307

days or longer is

nothing.

​(Round to four decimal places as​ needed.)

b. Babies who are born on or before

nothing

days are considered premature.

​(Round to the nearest integer as​ needed.)

2-

The lengths of pregnancies are normally distributed with a mean of

267267

days and a standard deviation of

1515

days. a. Find the probability of a pregnancy lasting

309309

days or longer. b. If the length of pregnancy is in the lowest

33​%,

then the baby is premature. Find the length that separates premature babies from those who are not premature.Click to view page 1 of the table.

LOADING...

Click to view page 2 of the table.

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a. The probability that a pregnancy will last

309309

days or longer is

nothing.

​(Round to four decimal places as​ needed.)

b. Babies who are born on or before

nothing

days are considered premature.

​(Round to the nearest integer as​ needed.)

3-

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

150150

lb and

191191

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

155 lb155 lb

and a standard deviation of

33.1 lb33.1 lb.

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

150150

lb and

191191

lb.The probability is approximately

nothing.

​(Round to four decimal places as​ needed.)b. If

3838

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

150150

lb and

191191

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 single pilot is more important.

B.

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

C.

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

D.

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

Answer 1