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December 19, 2014

December 19, 2014

Posted by **preston** on Thursday, October 2, 2008 at 4:33pm.

- math -
**Reiny**, Thursday, October 2, 2008 at 4:42pmSince the mean score of the 42 students was 75.5, the sum of all the scores of all students was 75.5(42)

let the number of students who passed be x

then 42-x must have failed

the sum of the scores of the passing students is then 81x, and

the sum of the scores of the failing students was (42-x)(60)

so isn't 81x + (42-x)(60) = (42)(75.5) ???

Take it from there

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