Question

Suppose a geyser has a mean time between eruptions of 84 minutes. If the interval of time between the eruptions is normally distributed with standard deviation 27 minutes A. Whats the probability that a random sample of 13 time intervals between eruptions has a mean longer than 95 minutes. B. Whats the probability that a random sample of 28 time intervals between eruptions has a mean time longer than 95 minutes. C. What effect does increasing the sample size have on the probability?

Answer 1

C) As the sample size increases, the probability being considered is getting lower. This makes sense

because as the sample size increases, the standard deviation of the sample mean distribution gets

smaller – resulting in less chance of moving far away from the mean.