Commuters were asked how many times a week they stop for coffee on their way to work. A survey found a mean of 3 times a week with a standard deviation of 0.55. Find the probability that the sum of 100 values is more than 290.

Question

Commuters were asked how many times a week they stop for coffee on their way to work. A survey found a mean of 3 times a week with a standard deviation of 0.55. Find the probability that the sum of 100 values is more than 290.

Answer 1

Z = (score-mean)/SEm = (2.9 - 3)/SEm

SEm = SD/√n

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z score.