There were 40 advance tickets sold, and 30 same-day tickets sold.
In order to find the average of all the costs, first you need to add up all of the expenditures from each month. (ex. 1,084.45+886.40+968.45+1,117.60+995.80+1,379.86) After you find the solution from adding those numbers together, divide the solution by the amount of costs there are in order to find the average. Since it was for 6 months, get the total from the addition problem and divide it by 6 and that will be your answer.
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
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Answer: The mean weight of the 20 backpacks is 11 pounds
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Sorry if it’s wrong but I think it’s like that