Weighted Mean (text p. 64-65) The following is a listing of raw material purchases by Acme Manufacturing over the past year: Purchase Cost Per Pound $ Number of Pounds 1 3.00 1200 2 3.40 500 3 2.80 2750 4 2.90 1000 5 3.25 800 Your boss wants you to calculate the mean cost of these raw materials. You could calculate the mean (arithmetic) by adding the five dollar amounts and dividing by 5 to get $3.07 per pound mean cost. However, this would not be the correct answer because you failed to account for the weighting (the number of pounds purchased at each price). Calculate the correct mean value for your boss by figuring the weighted mean cost per pound of this set of purchases: