A paint that is sold only in gallon containers covers 200 square feet

Question

A paint that is sold only in gallon containers covers 200 square feet per gallon of paint. How many gallons of the paint must be purchased to cover the walls of an auditorium that is 40 feet long, 25 feet wide, and 12 feet high if the areas of the windows and doors are ignored?

A. 4
B. 8
C. 16
D. 32
E. 60

PS21249

A. 4
B. 8
C. 16
D. 32
E. 60

PS21249

BrentGMATPrepNow · Accepted Answer

Here's an idea of what the auditorium looks like: 
 https://i.imgur.com/Adrwqvu.png

So the total surface area to be painted = (  12  )(  25  ) + (  12  )(  25  ) + (  12  )(  40  ) + (  12  )(  40  )
= 300 + 300 + 480 + 480
=  1560  square feet

Given: 1 gallon of paint covers 200 square feet

1560 /200 = 7.something
So, 7.something gallons of paint are needed. 
This means we must purchase  8  gallons of paint

Answer: B

Cheers,
Brent

IanStewart · Answer

Each of the four walls is 12 feet high. Two walls have a length of 40, and two have a length of 25, so the total surface area we need to cover is

(2)(40)(12) + (2)(25)(12) = (12)(80 + 50) = (12)(130) = 1560 square feet

So we'll need 8 of the 200-gallon cans of paint to cover that area (and since that would cover 1600 square feet, we'll have a bit of paint left over).

Babineaux · Answer

Four walls,
Two are L x H = 40 x 12 x 2 = 960 sq feet;
Two are B x H = 25 x 12 x 2 = 600 sq feet;

Total area of four walls, 960 + 600 = 1560 sq feet

Each container can be used to paint 200 sq feet;

Thus  \frac{1560}{200}  ~= 8 containers are required to paint four walls completely.

robinbjoern · Answer

I don't know where you come from but the top walls are also painted in Germany ^^

wishmasterdj · Answer

Exactly my thought. Seems to be a poor quality question. It should clearly specify the 4 walls. A question cant be made difficult by keeping ambiguity in its wording.

sonalchhajed2019 · Answer

How many gallons of the paint must be purchased to cover the walls of an auditorium that is 40 feet long, 25 feet wide, and 12 feet high if the areas of the windows and doors are ignored?
 Bunuel  in the above question, do we need to consider the area of walls and windows or do we need to ignore them? I understand that from the data given we will not be able to calculate the areas of windows and doors. But I had a hard time understanding the question. I do not know what the statement "if the areas of the windows and doors are ignored?" I feel it is open to 2 different interpretations.

Please guide.

02999 · Answer

Why we are not considering ceiling here ? Just because it's mentioned wall in the question stem?

IanStewart · Answer

Yes, that's right - the ceiling is not a wall, so it's not being painted here. If you weren't sure of that, and did the calculation counting the ceiling too, you won't get one of the answer choices, so if you thought the ceiling should maybe count, that's one way to see that it should not. And I'd bet they designed the answer choices with that in mind, because the GMAT isn't trying to 'trap' test takers who might reasonably think a ceiling is a wall.

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A paint that is sold only in gallon containers covers 200 square feet

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A paint that is sold only in gallon containers covers 200 square feet

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