Question 1076753: Mitchell has 18 bags of counters and 12 boxes of counters. T
The mean number of counters in the 18 bags is 10.
The mean number of counters in all 30 boxes and bags is 14.
Mitchell says "The mean number of counters per box is 4"
Is Mitchell's assumption correct? You must prove your answer.
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! mean=total/n
10=total/18
so 180 counters in the bags
in the 30 bags and boxes, the mean is 14, so there are 420 counters in both combined. Subtract the 180 that are known to be in the bags, and there are 240 in the boxes.
There are 12 boxes. Therefore, the mean number of counters per box is 20, 240/12.
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Check
If the mean is 10 in the bags, and the mean in both is 14, the mean has gone up when the boxes were added, so the boxes have to have a greater number to raise the mean, not a smaller number.
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