Radius of Circle

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Radius of Circle

by kanha81 » Wed Jun 24, 2009 9:06 am
Please see the attachment for the question.

How do you escape/decode trickery from such simple questions?
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Source: — Data Sufficiency |

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by Robinmrtha » Wed Jun 24, 2009 9:13 am
Statement 1
only the length of arc is given...
4 pi...Not sufficient

Statement 2
Center of circle is given...
Not sufficient to find the radius

combining both since the angle POQ is not given...
Not sufficient
Ans E

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by rookiez » Thu Jun 25, 2009 1:34 am
Trick here is not to Assume. GMAT is trying you to assume that the agnle is a right angle triangle. Don't go by figures unless it is stated.

if we can know the angle made by arc at the center then we can use the formula
Theta=Angle at center by an arc
[Theta/360]*2*pi*r=Lenght_of_arc

so in current Que answer is E