iikarthik wrote:At a certain hospital, 75% of the interns receive fewer than 6 hours of sleep and report feeling tired during their shifts. At the same time, 70% of the interns who receive 6 or more hours of sleep report no feelings of tiredness. If 80% of the interns receive fewer than 6 hours of sleep, what percent of the interns report no feelings of tiredness during their shifts?
6
14
19
20
81
Hi,
This is a MGMAT test Question.
Though the solution was given using some matrix method,i didnt get that.
can someone pls explain?
OA = 19
Thanks
karthik
In this problem we have two groups (those who got less than 6 hours sleep and those who got 6 hours or more) being further divided into smaller groups (those who were tired and those who were not).
When a problem discusses groups being further divided into smaller groups, use the group grid to organize the information.
The attached .pdf gives step by step instructions for filling out the grid. The idea is that all the numbers in the grid have to add up horizontally and vertically.
Hope this helps!
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Attachments
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- BTG_group_grid.pdf
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