Electricity bills in a certain city have mean $120.08. Assume the bills are normally distributed with standard deviation $14.40. Find the value that separates the lower 52% of the bills from the rest.

Answer 1

Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability (.52) and its Z score. Insert in above equation and solve for score.