DS question

Question

This is from the dreaded Kaplan CD, but I have a question about it. I knew that the answer was B, but I thought it could only be so if the line originated from the origin. Since this wasn't specified, I chose E, but I guess I out-thought myself.

On the real test, they will make it clear that the line originates from the origin, right???

Professor · Answer

nothing wrong with B. if c = d, then r = 45

microjohn · Answer

even if the line is not coming from the origin?

ps_dahiya · Answer

But its shown that its coming from origin. Question should have stated that line OX where O is the origin. Thats why I hate KAPLAN book. It tricks you on wording rather than concept.

microjohn · Answer

thanks dahiya. That's what I'm saying. Origin is not specified, and if you look at the line, it actually begins a little above the origin.

jaynayak · Answer

I know Kaplan sucks.... but IMO we can assume this. Right?

Futuristic · Answer

B.... I can see the confusion, I agree the diagram is a little messed up. Kaplan has ways to go.... :evil:

Professor · Answer

your question is valid. 

i also supposed that the line originated from the origin, we cannot suppose. so now st. 2 is also not suffcient. 1 and 2 are not suff. answer should be E.

the approach used in kaplan book is flawed..

yessuresh · Answer

Professor,

It can be easily inferred that O is the origin since X and Y axis are shown and the point where X and Y axis intersect is the origin. We dont have to suppose anything here. So, IMO the answer is B.

Professor · Answer

nope. you cannot make any supposition. ok, you can make inference but how do you infer that the line is originated from O (0,0)? you have to prove it.

either the question must provide or you should prove that the origin of the line is O (0,0).

this is a bad question at all.

kevincan · Answer

If the line doesn't originate from orgin, then what does angle r refer to? The arrows mean that the horizontal and vertical lines are the x and y axes. Cut us people at Kaplan some slack here, eh?

Professor · Answer

we can have a line passed from x=0 and y>0 with c=d where 0<r<180.

kevincan · Answer

Then r would be the angle between which two line segments?

Professor · Answer

r would be between y axis and the line that we draw from y axis..

kevincan · Answer

The diagram would have to be a lot more detailed if that were the case! Granted, the drawing could have been more carefully done. It was not Kaplan intention to mislead with it, though.

Professor · Answer

agreed.

but kaplan and TPR questions are not properly designed. particularly kaplan's questions are designed to give an impression that their questions are tough and standard but they actually are poorly structured. TPR is also not free from flaws. however, anybody can get trapped anywhere in gmat questions. cracking the gmat is not an easy job. :evil:

v1rok · Answer

I agree with majority and OP that this question (with the given answer by Kaplan) is misleading. Everywhere in the prep books it is said that on DS questions that have drawings and graphs you are not supposed to assume that the the graphs/pictures are drawn to scale. But apparently in order to solve this particular question the way Kaplan intended, one have to assume that the line is groing through the origin. I think they should change the wording of the question

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