Last visit was: 22 Dec 2024, 16:43 It is currently 22 Dec 2024, 16:43
Decision Tracker
My Rewards
New comers' posts
New posts
Unanswered

Close

GRE Prep Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GRE score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Go to My Error Log Learn more
Close

Request Expert Reply

Confirm Cancel
PREVIOUS TOPIC
NEXT TOPIC

Number of square tiles needed to cover a space on a wall of 72 x 108

Tags :
Find Similar Topics  About  Add a Tag

Show Tags
Hide Tags

User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30475
Own Kudos [?]: 36821 [1]
Given Kudos: 26100
Send PM
Number of square tiles needed to cover a space on a wall of 72 x 108 [#permalink] New post   Updated on: 16 Sep 2022, 07:59
Expert Reply
1
Bookmarks
00:00

Question Stats:

63% (02:06) correct 36% (02:32) wrong based on 22 sessions

Hide Show timer Statistics

Quantity A
Quantity B
Number of square tiles needed to cover a space on a wall of 72” x 108”, using tiles that each have a perimeter of 36 inches.
Number of square tiles needed to make a rectangular border one tile wide around the outside of the same 72” x 108” space, using tiles that each have an area of 9 square inches.



A. Quantity A is greater
B. Quantity B is greater
C. The two quantities are equal
D. The relationship cannot be determined from the information given

ShowHide Answer
Official Answer
B

Originally posted by Carcass on 06 Aug 2022, 00:41.
Last edited by Carcass on 16 Sep 2022, 07:59, edited 1 time in total.
Fixed OA
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30475
Own Kudos [?]: 36821 [0]
Given Kudos: 26100
Send PM
Re: Number of square tiles needed to cover a space on a wall of 72 x 108 [#permalink] New post   08 Aug 2022, 05:01
Expert Reply
Image



Replying to the question in 48 Hours

avatar
B
dc98
Intern
Intern
Joined: 08 Aug 2022
Posts: 23
Own Kudos [?]: 10 [1]
Given Kudos: 7
Send PM
Re: Number of square tiles needed to cover a space on a wall of 72 x 108 [#permalink] New post   03 Sep 2022, 03:01
1
For Quantity 1... Perimiter of tile is 36 so each side measures 9.. So area is 81...no of tiles required is 72*108/81=96

For Quantity 2...Area of tile is 9 so each side is 3..Now they are putting one tile extra on every side to increase width..Width is 72..So tiles required for one side is 72/3=24..Total 48 for two sides

hence A
avatar
B
pster79
Intern
Intern
Joined: 17 Jul 2022
Posts: 7
Own Kudos [?]: 3 [0]
Given Kudos: 6
GRE 1: Q167 V170
Send PM
Re: Number of square tiles needed to cover a space on a wall of 72 x 108 [#permalink] New post   16 Sep 2022, 07:07
Trying to figure out what I did wrong here. I got B .

A: length of one tile = perim / 4 = 9. tiles to cover width side =72/9 = 8 tiles to cover length side = 108/9 = 12. Whole area = 8*12 = 96
B: length of one tile = sqrt(area) = 3. tiles to cover width side =72/3 = 24 tiles to cover length side= 36. two sides each for rectangular border = 24*2 + 36*2 = 120
-- we already know B is greater, but to actually cover the whole border, we would need to cover the four corners with tiles too, bringing the total of B to 124.

did i misunderstand part of the question? Thanks
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30475
Own Kudos [?]: 36821 [0]
Given Kudos: 26100
Send PM
Re: Number of square tiles needed to cover a space on a wall of 72 x 108 [#permalink] New post   16 Sep 2022, 07:20
Expert Reply
OE


Quote:
Explanation: Read carefully – did you notice that the tiles specified in Column A had a perimeter of 36 inches, while the tiles in Column B were specified using their area? This is especially easy to miss since 36 is a perfect square. For Column A, the tiles have side length of 36/4 = 9”. You will need 72/9 = 8 tiles along the width, and 108/9 = 12 tiles along the length; (12)(8) = 96 tiles. Now, since the square border tiles have area of 9 square inches, they must have side length of 3”. The width can be bordered by 72/3 = 24 tiles, while the length can be bordered by 108/3 = 36 tiles. Don’t forget there are two lengths and two widths, for a total of 24 + 24 + 36 + 36 = 120 tiles. (You might also want to add another 4 tiles, for the corners, but it doesn’t make a difference for this problem.)

So more 3” small tiles are needed for the border (120) than large 9” tiles for the area (96). If you had used 6” tiles for the area as the problem attempted to mislead you, you would have needed 216 of them and mistakenly chosen A.
avatar
B
pster79
Intern
Intern
Joined: 17 Jul 2022
Posts: 7
Own Kudos [?]: 3 [1]
Given Kudos: 6
GRE 1: Q167 V170
Send PM
Re: Number of square tiles needed to cover a space on a wall of 72 x 108 [#permalink] New post   16 Sep 2022, 07:43
1
Carcass wrote:
OE


Quote:
Explanation: Read carefully – did you notice that the tiles specified in Column A had a perimeter of 36 inches, while the tiles in Column B were specified using their area? This is especially easy to miss since 36 is a perfect square. For Column A, the tiles have side length of 36/4 = 9”. You will need 72/9 = 8 tiles along the width, and 108/9 = 12 tiles along the length; (12)(8) = 96 tiles. Now, since the square border tiles have area of 9 square inches, they must have side length of 3”. The width can be bordered by 72/3 = 24 tiles, while the length can be bordered by 108/3 = 36 tiles. Don’t forget there are two lengths and two widths, for a total of 24 + 24 + 36 + 36 = 120 tiles. (You might also want to add another 4 tiles, for the corners, but it doesn’t make a difference for this problem.)

So more 3” small tiles are needed for the border (120) than large 9” tiles for the area (96). If you had used 6” tiles for the area as the problem attempted to mislead you, you would have needed 216 of them and mistakenly chosen A.


Thanks for posting this, but does this mean the answer should be B (the Show Answer link above shows A)? Thx
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30475
Own Kudos [?]: 36821 [0]
Given Kudos: 26100
Send PM
Re: Number of square tiles needed to cover a space on a wall of 72 x 108 [#permalink] New post   16 Sep 2022, 07:58
Expert Reply
pster79 wrote:
Carcass wrote:
OE


Quote:
Explanation: Read carefully – did you notice that the tiles specified in Column A had a perimeter of 36 inches, while the tiles in Column B were specified using their area? This is especially easy to miss since 36 is a perfect square. For Column A, the tiles have side length of 36/4 = 9”. You will need 72/9 = 8 tiles along the width, and 108/9 = 12 tiles along the length; (12)(8) = 96 tiles. Now, since the square border tiles have area of 9 square inches, they must have side length of 3”. The width can be bordered by 72/3 = 24 tiles, while the length can be bordered by 108/3 = 36 tiles. Don’t forget there are two lengths and two widths, for a total of 24 + 24 + 36 + 36 = 120 tiles. (You might also want to add another 4 tiles, for the corners, but it doesn’t make a difference for this problem.)

So more 3” small tiles are needed for the border (120) than large 9” tiles for the area (96). If you had used 6” tiles for the area as the problem attempted to mislead you, you would have needed 216 of them and mistakenly chosen A.


Thanks for posting this, but does this mean the answer should be B (the Show Answer link above shows A)? Thx


:(

The answer is indeed B but the book reports A in the OA. The explanation B
Prep Club for GRE Bot
gmatclubot
Re: Number of square tiles needed to cover a space on a wall of 72 x 108 [#permalink]
16 Sep 2022, 07:58
Moderators:
adewale223
GRE Instructor
88 posts
bronaugust
GRE Forum Moderator
37 posts
BrushMyQuant
Moderator
1115 posts
VibhuAnurag
GRE Instructor
234 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Main navigation

Partners

GRE Resources

www.ets.org/gre | About | Terms and Conditions and Privacy Policy | Prep Club for GRE Rules | Contact