A square wooden plaque has a square brass inlay in the center, leaving a wooden strip of uniform width around the brass square. lf the ratio of the brass area to the wooden area is 25 to 39, which of the following could be the width, in inches, of the wooden strip?
i. 1
ii. 3
iii. 4
(A) I onlY
(B) ll onlY
(C) I and ll only
(D) I and lll only
(E) l, ll, and lll
Original explanation is waaaaaayyyy to lengthy!Any simple method. Rather is there any conceptual approach to such problems?
Geometry
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This is a bit of a trick question.vinay1983 wrote:A square wooden plaque has a square brass inlay in the center, leaving a wooden strip of uniform width around the brass square. lf the ratio of the brass area to the wooden area is 25 to 39, which of the following could be the width, in inches, of the wooden strip?
i. 1
ii. 3
iii. 4
(A) I onlY
(B) ll onlY
(C) I and ll only
(D) I and lll only
(E) l, ll, and lll
We have a brass square inside a wood frame. The ratio of the brass area to the wooden area is 25 to 39.
Once we find a width of the wooden strip that works, we can shrink or expand size of the plaque to get ANY width.
In other words, the wooden strip can have ANY length.
Answer: E
Cheers,
Brent
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Here are some diagrams to support the solution in my last post.vinay1983 wrote:A square wooden plaque has a square brass inlay in the center, leaving a wooden strip of uniform width around the brass square. lf the ratio of the brass area to the wooden area is 25 to 39, which of the following could be the width, in inches, of the wooden strip?
i. 1
ii. 3
iii. 4
(A) I onlY
(B) ll onlY
(C) I and ll only
(D) I and lll only
(E) l, ll, and lll
Let's say we want to create a plaque with a square brass inlay in the center, and we want the brass to wood ratio to be 25:39
Let's begin a square wooden board with ANY dimensions.
Now place a square brass inlay in the middle of the wooden board, and keep adjusting the size of the brass inlay until we have a brass to wood ratio that is 25:39
At this point, if we shrink or expand the plaque . . .
. . . the brass to wood ratio will remain at 25:39
So, as you can see, this plaque can be ANY size, which means the width of the wooden strip can have ANY measurement.
Answer: E
Cheers,
Brent
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See here for a virtually identical question/discussion: https://www.beatthegmat.com/ds-geometry-t284497.html
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Evinay1983 wrote:A square wooden plaque has a square brass inlay in the center, leaving a wooden strip of uniform width around the brass square. lf the ratio of the brass area to the wooden area is 25 to 39, which of the following could be the width, in inches, of the wooden strip?
i. 1
ii. 3
iii. 4
(A) I onlY
(B) ll onlY
(C) I and ll only
(D) I and lll only
(E) l, ll, and lll
Original explanation is waaaaaayyyy to lengthy!Any simple method. Rather is there any conceptual approach to such problems?
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
GMAT/MBA Expert
- Brent@GMATPrepNow
- 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
See my posts aboverupalie wrote:Thanks Brent, can you please explain...thanks!