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## Comment on

Double Matrix Method## Another method shows the

## That method is exactly the

That method is exactly the same. The only difference is a small change in how we show the totals for each row and column.

## For the motel ques below, the

One night a certain motel rented 3/4 th of its rooms, including 2/3rd of its air-conditioned rooms. If 3/5th of its rooms were air-conditioned, what percent of the rooms that were not rented were air-conditioned?

## You're referring to this

You're referring to this question: http://www.beatthegmat.com/motel-t271938.html

This is an official GMAT question, and I think the wording is fine. We're told that 2/3 of the air-conditioned rooms were rented, so I'm not sure what could be changed to make it more readable.

## Hi, Brent! I used the double

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?

A) 6

B) 14

C) 19

D) 20

E) 81

Answer C

## Hi Jingyjess,

Hi Jingyjess,

The key word here is AND: "At a certain hospital, 75% of the interns receive fewer than 6 hours of sleep AND report feeling tired during their shifts."

If the test-makers wanted to convey your interpretation, they'd write "OF THE interns who received fewer than 6 hours of sleep, 75% report feeling tired during their shift." (Notice that's there's no AND here. Instead, we have OF THE)

Does that help?

Cheers,

Brent

## Thank you for the feedback!I

## Hey Brent,

Please help me with the following question posted on Beat the GMAT. I am extremely confused wrt using the double matrix method for this.

At least 100 students at a certain high school study Japanese. If 4 percent of the students at the school who study French also study Japanese, do more students at the school study French than Japanese?

(1) 16 students at the school study both French and Japanese.

(2) 10 percent of the students at the school who study Japanese also study French.

Thanks in advance,

Aashay

## Hi Aashay,

Hi Aashay,

I'm happy to help.

You'll find my solution here: http://www.beatthegmat.com/at-least-100-students-at-a-certain-high-schoo...

Cheers,

Brent

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