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1 vote
What number does someone need on the next test to keep the 81 mean if the past 3 tests had

59, 87, 97

User Nmio
by
5.3k points

1 Answer

7 votes
81,

First, reverse the mean equation of sum of all #’s divided by the # of #’s to the mean times the # of #’s to get the sum of all numbers.

81*4=324

Then we subtract the sum of the three #’s.

324-243=81
User Lex Podgorny
by
5.4k points
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