Parents supervise - overlapping sets

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Parents supervise - overlapping sets

by GmatGreen » Fri Feb 21, 2014 8:17 am
Of the 84 parents who attended a meeting at the school, 35 volunteered to supervise children during the school picnic and 11 volunteered both to supervise children during the picnic and to bring refreshments to the picnic. If the number of parents who volunteered to bring refreshments was 1.5 times the number of parents who neither volunteered to supervise children during the picnic nor volunteered to bring refreshments, how many of the parents volunteered to bring refreshments?

A) 25
B) 36
C) 38
D) 42
E) 45

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by Patrick_GMATFix » Fri Feb 21, 2014 8:35 am
Overlapping sets can usually be solved quickly by arranging data in a table, drawing Venn diagrams or using the overlapping groups formula. The full solution below is taken from the GMATFix App.

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