Gmat Prep Test 2 - Distance between two points-tricky

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Q) A certain circular area has its center at point b and has radius 4, and points X and Y lie in the same plane as the circular area. Does Point Y lie outside the circular area.

1) The dis between P and X is 4.5

2) The dis between X and Y is 9.


So we know that X is outside from 1 but that it. So insuff

Sec one tells us about x and y but nothing circle so insuff

together-x is 4.5 away from center of circle and Y is 9 away from X. But what direction. I would think insuff

OA is C.

I think it should be E as we cannot determine which side of X is Y or any direction so may or may not lie outside the circular area.





Thanks
Khurram
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khurram wrote:Q) A certain circular area has its center at point b and has radius 4, and points X and Y lie in the same plane as the circular area. Does Point Y lie outside the circular area.

1) The dis between P and X is 4.5

2) The dis between X and Y is 9.


So we know that X is outside from 1 but that it. So insuff

Sec one tells us about x and y but nothing circle so insuff

together-x is 4.5 away from center of circle and Y is 9 away from X. But what direction. I would think insuff

OA is C.

I think it should be E as we cannot determine which side of X is Y or any direction so may or may not lie outside the circular area.

Thanks
Khurram
First, I'm going to assume that statement (1) should read "The distance between b and X is 4.5" (since we've never heard of "P" before).

So, we know that X is 4.5 units from the Centre.

(2) alone, nothing to relate X and Y to the circle.

Together: if Y is 9 units away from X, no matter which direction you go Y will also be outside the circle.

For example, if we draw a straight line from X --- b ----- Y, we'll see that Y is 4.5 units away from the centre.

Any other line we draw will put Y even further away from b. Therefore, Y is definitely NOT inside the circle: choose (C).
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by khurram » Mon Jun 02, 2008 7:46 pm
thanks Stuart
This was a hard one.

Khurram