Item 7
A collection of 8 backpacks has a mean weight of 14 pounds. A different collection of 12 backpacks has a mean weight of 9 pounds. What is the mean weight of the 20 backpacks?
Total weight of the 8 backpacks = 8 x 14 = 112 pounds
Total weight of the 12 backpacks = 12 x 9 = 108 pounds
Total weight of all the 20 backpacks = 220 pounds
Mean weight of the 20 backpacks = 220 ÷ 20 = 11 pounds
---------------------------------------------------------------------------------------- Answer: The mean weight of the 20 backpacks is 11 pounds ----------------------------------------------------------------------------------------