Probability Cordinate geometry : TOUGH

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Probability Cordinate geometry : TOUGH

by maihuna » Fri Dec 25, 2009 10:23 am
A rectangle centered at origin has following four vertices (-2,1) (2,1) (2, -1) (-2, -1). If a point fall on the rectangular region at random, what is the probability that the ordinates of the point will satisfy that x+y > 1.

1/4
1/3
1/2
2/3
3/4
Charged up again to beat the beast :)
Source: — Data Sufficiency |

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by linkinpark » Sat Dec 26, 2009 1:12 am
is it A?
I drew a fictional rectangle using mentioned coordinates and I think points that fall in first quadrant i.e. both x and y positive satisfy the equation but I'm doubtful if the answer choice are correct.
the reason is within the first quadrant also there are points where x+y<1 but if question is correct then A is my pick

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by linkinpark » Sat Dec 26, 2009 2:41 am
my bad I was wrong in stating that only points in quarter 1 satisfy the equation, I thought more about it

some region in quarter 1 and some in quarter 4 will satisfy the equation. but I still stand with my answer pick to be 1/4 (A).