scottchapman wrote:Thank you all for your responses. I struggle with DS and I think part of the reason for it is not rewording the question effectively. It makes sense after I see you guys go through the steps, but for whatever reason, I continue to make the same errors. I'm assuming I just need more practice...
The geometry problem above is a VALUE DS: a DS whose question stem asks for a specific value.
One way to evaluate the statements -- and to avoid falling for a trap -- is to TEST TWO CASES.
If the desired value is THE SAME in each case, the statement is SUFFICIENT.
If the desired value is NOT the same in each case, the statement is INSUFFICIENT.
If L & W represent the length and width, respectively, of the rectangle above, what is the perimeter?
1). 2L + W = 40
2). L + W = 25
Statement 1: 2L + W = 40
Case 1: L=10, W=20, with the result that 2L + W = 2*10 + 20 = 40
The following rectangle is yielded:
Case 2: L=5, W=30, with the result that 2L + W = 2*5 + 30 = 40
The following rectangle is yielded:
Since the perimeter is NOT the same in each case, INSUFFICIENT.
Statement 2: L+W = 25
Case 3: L=10, W=15
The following rectangle is yielded:
Case 4: L=5, W=20
The following rectangle is yielded:
Since the perimeter is THE SAME in each case, SUFFICIENT.
The correct answer is
B.
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