The typical American generates about 3.8 pounds of solid trash per day with a standard deviation of 1.5 pounds. Assuming that the histogram for trash produced per day is aprox. bell shaped, between what two values will 95% of the observtion fall?
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the Z score related to those proportions (±.25%). Put values in equation below.
Z = (score-mean)/SD