In the figure above, what is the ratio KN/MN ?
1) The perimeter of rectangle KLMN is 30 meters.
2) The three small rectangles have the same dimensions.
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ratio of rectangle sides
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LulaBrazilia
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In the figure above, what is the ratio KN/MN ?
1) The perimeter of rectangle KLMN is 30 meters.
2) The three small rectangles have the same dimensions.
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Patrick_GMATFix
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statement 1 just tells us that 2(KN + MN) = 30. We can come up with a lot of values for KN and MN that would result in different ratios, so that statement is not helpful. Statement 2 is more interesting. If all the rectangles are the same, we can start to label sides using only two variables (for width and length) and perhaps even find out the ratio KN/MN. The full solution below is taken from the GMATFix App.
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Brent@GMATPrepNow
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Target question: what is the ratio KN/MN?LulaBrazilia wrote:
In the figure above, what is the ratio KN/MN?
1) The perimeter of rectangle KLMN is 30 meters.
2) The three small rectangles have the same dimensions.
Statement 1: The perimeter of rectangle KLMN is 30 meters.
This doesn't tell us much. Consider these two possible cases (among many)
case a:
Here the ratio KN/MN = 1/14
case b:
Here the ratio KN/MN = 7/8
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: The three small rectangles have the same dimensions.
Let x = length of shorter side of 1 rectangle:
Since 3 rectangles have the same dimensions, we can add x to another side:
Notice that that this means that side KN has length 2x.
Since 3 rectangles have the same dimensions, we can add 2x to another side:
At this point, we can see that side MN has length 3x
From here, we can see that the ratio KN/MN = 2x/3x = 2/3
Since we can answer the target question with certainty, statement 2 is SUFFICIENT
Answer = B
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
