Question

Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean of μ=271 days and standard deviation o=26 days. Complete parts​ (a) through​ (f) below.

​(a) What is the probability that a randomly selected pregnancy lasts less than 263 days?

The probability that a randomly selected pregnancy lasts less than 263 days is approximately 0.3783.

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

Interpret this probability. Select the correct choice below and fill in the answer box within your choice.

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

A. If 100 pregnant individuals were selected independently from this​ population, we would expect

_____pregnancies to last less than 263

days.

B.If 100 pregnant individuals were selected independently from this​ population, we would expect ___

pregnancies to last exactly 263 days.

C.If 100 pregnant individuals were selected independently from this​ population, we would expect ____

pregnancies to last more than 263 days.

Which one and what is the number?

Answer 1

Given that, mean = 271 days

standard deviation = 26 days

a) P(X < 263) = 0.3783

sample size ( n ) = 100

Here, 100 * 0.3783 = 37.83 (approx 38)

Therefore, if 100 pregnant individuals were selected independently from his population, we would expect 38 pregnancies to last less than 263 days.