In: Statistics and Probability
The average number of pounds of meat that a person consumes per year is 218.4 pounds. Assume that the standard deviation is 25 pounds and the distribution is approximately normal.
a) Find the probability that a person selected at random consumes less than 224 pounds of meat per year. Calculate the z-score manually, and use StatCrunch or the Standard Normal Table to calculate the probability, rounding to four decimal places. (4 points)
b) If a sample of 40 individuals were selected randomly, find the probability that the mean of the sample will be less than 224 pounds per year. Calculate the z-score manually, and use StatCrunch or the Standard Normal Table to calculate the probability, rounded to four decimal places. (4 points)
c) Why are the probabilities in parts (a) and (b) so different? (2 points)