The seating chart of an airplane shows 30 rows of seats

Question

The seating chart of an airplane shows 30 rows of seats. Each row has 3 seats on each side of the center aisle, and one of the seats on each side is a window seat. The view from the window seats in 5 of the rows is obscured by the wings of the airplane. If the first person to be assigned a seat is assigned a window seat and the window seat is assigned randomly, what is the probability that the person will get a seat with an unobscured view?

A. 1/6
B. 1/3
C. 2/3
D. 5/6
E. 17/ 18

A. 1/6
B. 1/3
C. 2/3
D. 5/6
E. 17/18

Bunuel · Answer

The total number of window seats is 30 * 2 = 60.
The number of window seats with an obscured view is 5 * 2 = 10, so the number with an unobscured view is 60 - 10 = 50.

Probability = favorable/total = 50/60 = 5/6.

Answer: D.

GMATD11 · Answer

Pls correct if m wrong

Total number of window seats 30+30 = 60(on both sides of the aisle
 Obscured on both sides 5+5 =10 
 Unobscured on both sides =50

Probability = unobscured /total window seats
 50/60 = 5/6

dchow23 · Answer

How come you didn't consider 6 seats per row? Isn't that what is stated in the question? I know the numbers workout the same but still.

# of Total seats = 30(3)(2) = 180

Window seats = 60
Obstructed view window seat = 10

Since the question tells us that a window seat was obtained, all we care about are the window seats

Therefore probability of unobstructed view = 60-10/60 = 5/6 D

Is this reason of thinking correct? or the above is better?

Kinshook · Answer

Given: The seating chart of an airplane shows 30 rows of seats. Each row has 3 seats on each side of the center aisle, and one of the seats on each side is a window saet. The view from the window seats in 5 of the rows is obscured by the wings of the airplane.

Asked: If the first person to be assigned a seat is assigned a window seat and thw window seat is assigned randomly, what is the probability that the person will get a seat with an unobscured view?

Total number of window seats = 30*2 = 60
Number of window seats with obscured view = 5*2 = 10
Number of window seats with unobscured view = 60 - 10 = 50

The probability that the first person with get a seat with an unobscured view = 50/60 = 5/6

IMO D

Fish181 · Answer

I was under the impression that PS questions only give you information you NEED to solve and are unlike DI questions in the sense they don't give you extra info to "bog you down". It seems pretty clear to me the point of this question is to do just that and throw you off by including unnecessary info.

DmitryFarberMPrep · Answer

This does have more extraneous information than we'd typically see in a PS question, but the test does sometimes throw in some distractions. This certainly becomes very relevant on DI, where there's going to be a whole lot more information than we have time to deal with.

rak08 · Answer

if total seats are 180,
window seats are 2*30 = 60
Ob window = 5*2 = 10
unob = 50

so isn't the probab = 50/180 = 5/18??

why am I wrong ?? please guide  Bunuel   KarishmaB

Bunuel · Answer

You're dividing by 180, but the question says the seat is chosen from window seats only, not all 180 seats.

There are 60 window seats, and 50 of them have an unobscured view.

So the probability = 50/60 = 5/6.

The seating chart of an airplane shows 30 rows of seats

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GMAT Problem Solving (PS) Questions

The seating chart of an airplane shows 30 rows of seats

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