The weights of cereal boxes was found to be normally distributed. The mean is 16 oz and the standard deviation is 0.5 oz. From a sample of 250 boxes about how many should weigh between 15.5 oz and 17 oz?

Answer 1

Z = (score-mean)/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 between the two Z scores. Multiply by 250.

Answer 2

203 boxes

Answer 3

40