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probability (plane)

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by DanaJ » Fri Jan 23, 2009 1:45 pm
I would say that the probability is 1, meaning that all points P(x,y) with x^2+ y^2 = 1. What is the OA?

This is easily explained by the formula. x^2 + y^2 =1 is actually the equation of a circle with O(0,0) (center of circle) and radius 1. A radius of 1 means that the circle will "touch" our square in four points: (1,0), (-1,0), (0,1), (0,-1) and be inscribed in the circle.

The general formula for a circle is (x - a)^2 + (y - b)^2 = r^2, with r = radius and O(a,b) the center of the circle.
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by aroon7 » Fri Jan 23, 2009 5:16 pm
it will be area of circle/Area of the square
radius of circle is 1 and side of the square is 2
so answer is pi/4

what is the OA?
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by awesomeusername » Fri Jan 23, 2009 7:50 pm
I'm going to have to agree with Dana here. If the circle in inscribed in the square, then that would mean that all points fall within the bounds of the square, so the probability would have to be 1, right?
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by DanaJ » Fri Jan 23, 2009 10:44 pm
The formula that aroon7 provided actually represents the probability of a point in the square to be in the circle also. The question is about points in the circle that fall in to the square, IMHO....
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by aroon7 » Sat Jan 24, 2009 7:21 am
DanaJ wrote:The formula that aroon7 provided actually represents the probability of a point in the square to be in the circle also. The question is about points in the circle that fall in to the square, IMHO....
you are right danaj...
i misunderstood the question.
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by mariah » Thu Jan 29, 2009 2:33 pm
oa pai/4
I have collected it from internet so oa may be inaccurate,
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by krisraam » Thu Jan 29, 2009 8:32 pm
Answer is 1
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