question about interns

5abi 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
8

tricky question: OA C

I normally solve it this way


Manhattan double matrix also does the same

2 things to remember
some percent given are not of total for eg 70% given here is not of 100%9
You dont need to start as information are ordered.In this qustion if you start from 20%-80%(which has been given later) things it will be easier

Fewer than 6 Hours of Sleep, ------- >6 More than 6 Hours of Sleep, --------- <6

Tired 5 + 14 = 19

Not Tired 75 + 6 = 81
---------- -------------- ----------------
80 20 100


Hope this Helps...