QUANT DS

This topic has expert replies
Senior | Next Rank: 100 Posts
Posts: 87
Joined: Sun Jul 24, 2011 10:36 am

QUANT DS

by [email protected] » Wed Sep 07, 2011 5:41 am
Q: A rectangular floor is to be covered with square tiles, such that the no square tiles
Overlap each other. Is 150 tiles enough to cover the floor?
A: The perimeter of each tile is 4
B: The perimeter of rectangle is 50

my answer is EE
Source: — Data Sufficiency |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pm
Location: Vancouver, BC
Thanked: 5254 times
Followed by:1268 members
GMAT Score:770

by Brent@GMATPrepNow » Wed Sep 07, 2011 5:53 am
[email protected] wrote:Q: A rectangular floor is to be covered with square tiles, such that the no square tiles
Overlap each other. Is 150 tiles enough to cover the floor?
A: The perimeter of each tile is 4
B: The perimeter of rectangle is 50
We should recognize that, to answer the target question, we need information about the area of each tile and the area of the floor.

As such, we can quickly see that each statement alone is insufficient. This means the answer is either C or E.

Now let's combine the statements.

Statements 1 & 2:
From statement 1, we know that each square tile has dimensions 1x1
Statement 2 allows us to consider (at least) two cases:

case a: the floor has dimensions 24x1, in which case, we would need 24 tiles to cover the floor.
In this case, the answer to the target question is YES, 150 tiles is enough to cover the floor.

case b: the floor has dimensions 12.5x12.5, in which case, we would need 169 tiles to cover the floor.
Aside: We would need 13 tiles to cover the width of the floor and 13 tiles to cover the length of the floor. So, the total number of tiles required would equal 169 (13x13=169)
In this case, the answer to the target question is NO, 150 tiles is not enough to cover the floor.

Since we cannot answer the target question with certainty, the answer is E.

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image

User avatar
Legendary Member
Posts: 1309
Joined: Mon Apr 04, 2011 5:34 am
Location: India
Thanked: 310 times
Followed by:123 members
GMAT Score:750

by cans » Wed Sep 07, 2011 7:08 am
IMO E
If my post helped you- let me know by pushing the thanks button ;)

Contact me about long distance tutoring!
[email protected]

Cans!!