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the circle it belongs to

by sanju09 » Tue Apr 13, 2010 5:24 am
How far is point P from point Q?

(1) Chord PQ is same as radius and area of the circle it belongs to.

(2) Major-arc PQ of the circle it belongs to is 5/3.
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by ymach3 » Tue Apr 13, 2010 6:33 am
Is the answer - A ?


PQ= (Pi)^-1 ---> from S (i)

S(ii) - Insufficient as R and angle are unknown.

Please correct me if i did a blunder ...
Last edited by ymach3 on Tue Apr 13, 2010 7:38 am, edited 1 time in total.
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by Fiver » Tue Apr 13, 2010 7:25 am
Agree with A.

St1] suggest that the lenght of PQ is 7/22

St2] is insufficient as it suggests more than one possibility-

e.g. the minor arc could be 90, making the triangle a 45-45-90 triangle and PQ = root2 * r
or the triangle could be an equilateral triangle, making PQ = r = 7/22

What's the OA?
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by eaakbari » Tue Apr 13, 2010 8:29 am
sanju09 wrote: (1) Chord PQ is same as radius and area of the circle it belongs to.
.

I cannot comprehend this statement. Someone please explain
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by Cdawg » Tue Apr 13, 2010 9:12 am
sanju09 wrote:How far is point P from point Q?

(1) Chord PQ is same as radius and area of the circle it belongs to.

(2) Major-arc PQ of the circle it belongs to is 5/3.
Statement 1:

if Area = radius = chord, it follows that A = r = Pi*r^2 => r=1/Pi so chord is 1/Pi No other circle fulfills the requirement that area equals radius. So the statement is sufficient

Statement 2: tells you that the major arc is 5/3 long. Well you don't know where the points are located on the circle. => insufficient

I think the question tries to trick you into combining both statements. Then you can also solve for it using the 5/3 that account for 5/6th of the whole circumference, which you can use to calculate the radius = chord. At least it tricked me ;)

well, i agree with the previous posters
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by Cdawg » Tue Apr 13, 2010 9:12 am
eaakbari wrote:
sanju09 wrote: (1) Chord PQ is same as radius and area of the circle it belongs to.
.

I cannot comprehend this statement. Someone please explain
chord = radius = area
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by kstv » Tue Apr 13, 2010 9:31 am
sanju09 wrote:How far is point P from point Q?
(1) Chord PQ is same as radius and area of the circle it belongs to.
(2) Major-arc PQ of the circle it belongs to is 5/3.
(1) Length of PG = r = Pi r²
Pi r² - r = 0 r(22/7*r-1) = 0 so r = 7/22
Suff
(2) PQ = r if o is the centre of the circle PO= OQ = PQ
POQ is a equilateral triangle and angle POQ is 60°
so minor arc PQ is 1/6 of 2pi r
and major arc = 5/6 * 22/7 * 2 * r = 5/3
or r= 7/22 Suff
IMO D
Great Q
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by sanju09 » Thu Apr 15, 2010 12:30 am
kstv wrote:
sanju09 wrote:How far is point P from point Q?
(1) Chord PQ is same as radius and area of the circle it belongs to.
(2) Major-arc PQ of the circle it belongs to is 5/3.
(1) Length of PG = r = Pi r²
Pi r² - r = 0 r(22/7*r-1) = 0 so r = 7/22
Suff
(2) PQ = r if o is the centre of the circle PO= OQ = PQ
POQ is a equilateral triangle and angle POQ is 60°
so minor arc PQ is 1/6 of 2pi r
and major arc = 5/6 * 22/7 * 2 * r = 5/3
or r= 7/22 Suff
IMO D
Great Q
How is (2) alone sufficient? Is it (1)'s hangover or something?
The mind is everything. What you think you become. -Lord Buddha



Sanjeev K Saxena
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