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.
Target question: what is the ratio KN/MN?
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
