Two DS Question

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Two DS Question

by reachac » Wed Jul 23, 2008 5:03 am
Please help with these two questions.[/img]
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by cubicle_bound_misfit » Wed Jul 23, 2008 6:59 am
Hello Sir,

For the geometry q is the answer D?

Please let me know OA.

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by reachac » Wed Jul 23, 2008 7:10 am
Yups OA is D, but how did u get that, I thot it should have been E coz I could find no way to get the area of the sector OAX. where X is the point of intersection of the diagonal and the circle.

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by cubicle_bound_misfit » Wed Jul 23, 2008 7:43 am
you owe me one :-) https://www.beatthegmat.com/set-q-1-t14264.html#58978


for the semicircle lenght of sector pi*R

you have to substract the rest of the sector with inscribed angle 45 degree.


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by reachac » Wed Jul 23, 2008 9:36 am
Ohh u remember that question :), well had sent u a PM explaining my stance.

Nehw comin back to this question, how can u say that OAX is a quarter circle (or for that matter how can u say that the inscribed angle is 45 degree) I see no basis for this being provided by the question or the options.

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by cubicle_bound_misfit » Wed Jul 23, 2008 11:05 am
I am not saying oax is. I am saying the rest of the thing is.
So OAX = (length of semicircle - sector that has an inscribed angle of 45 degs.)

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by Canman » Wed Jul 23, 2008 11:43 am
I think the ans on Q1 is E

Stem: We need to find number presents to wrap and range of presents that can be wrapped in 1 hr based on number of clerks available to wrap presents, to determine sufficiency.

1) tells us # range of presents that can be wrapped in 1 hr but not # of presents - INSUFFICIENT

ex: 6 clerks can wrap 120-180 presents in 1 hour

2) tells us # range of presents but not # of clerks available - INSUFFICIENT

ex: 70(p+1)=9(20), 70p=110=total presents to wrap based on rate of 20 per hour, or it may be 70(p+1)=9(30), 70p=200=total presents to wrap based on rate of 30 per hour

1+2) INSUFFICIENT because we know the clerks can wrap up to 180 per hour but we don't know if the shoppers have 110 or 200 presents to wrap

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by reachac » Wed Jul 23, 2008 8:41 pm
cubicle_bound_misfit wrote:I am not saying oax is. I am saying the rest of the thing is.
So OAX = (length of semicircle - sector that has an inscribed angle of 45 degs.)

regards,
Well I'm really sorry but somehow I cannot see which 45 degree incribed angle are you referring to and how did you get measure of that angle. are you assuming that OX is perpendicular to AB, if yes then what basis?

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by airan » Thu Jul 24, 2008 2:45 am
Asnwer for gift wrapping should be C ..
What is the OA ..and from next time onwards, pls avoid 2 questions in the same post...!
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Airan

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by airan » Thu Jul 24, 2008 2:58 am
Assuming AC cuts the semicircle at X, we wud need angle AOX to find the area of the minor sector AX.
A similar diagonal DB will also cut the circle at X( it being a square on diameter).

Now the area of semicircle is= are of triangle AXB plus 2 small sectors.
Area of triangle AXB can be found ..as it will be right triangle ..Hence area of the shaded region can be found .

B gives the same info as A hence D.
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Airan