Suppose a random sample of 25 students is selected from a community college where the scores in the final exam (out of 125 points) are normally distributed, with mean equal to 112 and standard deviation equal to 12. Find the probability that the sample mean deviates from the population mean μ = 112 by no more than 4.

Answer 1

Z = (score-mean)/SD

Solve for scores of 116 and 108.

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