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The mean of 16 items was found to be30. ...

The mean of 16 items was found to be30. On rechecking, it was found that two items were wrongly taken as 22 and 18 instead of 32 and 28, respectively. Find correct mean.

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Mean`=`Sum`/`Total items
Sum`=`Mean`xx`Total items
Incorrect sum`=16xx30=480`
Correct mean`=(480-(22+18)+(32+28))/16`
`=(480+60-40)/16
`
`=(480+20)/16`
`=500/16=31.25`
`:.` Correct mean`=31.25`
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