Hello BTG
Would appreciate a little help on the question below, and especially why C is not the right answer.
My approach here is, that combined we know that the "3-4-5"-triangle is a right triangle (or is it ?).
Since we know that the diameter is AB (and therefore the longest line possible inscribed in the circle), we can determine the diameter to 5, and through this calculate the circumference.
Thanks in advance
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GMAT Exam pack 2 - DS - Geometry
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DavidG@VeritasPrep
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The ratio of the sides is 3:4:5, not the actual measurements. In other words, the actual measurements could be 3, 4, and 5 or they could be 6, 8, and 10, or 9, 12, 15, etc.lucas211 wrote:Hello BTG
Would appreciate a little help on the question below, and especially why C is not the right answer.
My approach here is, that combined we know that the "3-4-5"-triangle is a right triangle (or is it ?).
Since we know that the diameter is AB (and therefore the longest line possible inscribed in the circle), we can determine the diameter to 5, and through this calculate the circumference.
Thanks in advance
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ceilidh.erickson
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David is absolutely right about the ratio v. length.lucas211 wrote:Hello BTG
Would appreciate a little help on the question below, and especially why C is not the right answer.
My approach here is, that combined we know that the "3-4-5"-triangle is a right triangle (or is it ?).
Since we know that the diameter is AB (and therefore the longest line possible inscribed in the circle), we can determine the diameter to 5, and through this calculate the circumference.
Thanks in advance
One thing I want to add: If statement 2 had told us that the lengths were 3, 4, and 5, we wouldn't actually have needed statement 1 as well. Any triangle that has side lengths in the ratio 3:4:5 must be a right triangle (just as any triangle with 3 equal sides must be equilateral). If we knew it was a right triangle, then we'd know that the hypotenuse must be the diameter of the circle.
Ceilidh Erickson
EdM in Mind, Brain, and Education
Harvard Graduate School of Education
EdM in Mind, Brain, and Education
Harvard Graduate School of Education
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Matt@VeritasPrep
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If the ratio is 3:4:5, we could have 3:4:5, or 6:8:10, or 9:12:15, or ...
The devil is in the details!
As a general strategy tip, if a DS question seems to be an obvious C, run screaming from answer C!
The devil is in the details!
As a general strategy tip, if a DS question seems to be an obvious C, run screaming from answer C!
