Question

Suppose a geyser has a mean time between eruptions of 86 minutes. Let the interval of time between the eruptions be normally distributed with standard deviation 19 minutes. Complete parts ​(a) through ​(e) below.

(a) What is the probability that a randomly selected time interval between eruptions is longer than 94 minutes?

(b) What is the probability that a random sample of 9 time intervals between eruptions has a mean longer than 94 ​minutes?

(c) What is the probability that a random sample of 31 time intervals between eruptions has a mean longer than 94

​minutes?

(d) What effect does increasing the sample size have on the​ probability? Provide an explanation for this result.

(e) What might you conclude if a random sample of 31 time intervals between eruptions has a mean longer than 94 minutes?

Answer 1