Data suffiency.

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Data suffiency.

by Md.Nazrul Islam » Sun Apr 01, 2012 5:07 am
If L1,L2,L3 are lines in a plane is L1 perpendicular to L3?

1) L1 is perpendicular to L2 .

2)L2 is perpendicular to L3.

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by Pharo » Sun Apr 01, 2012 5:32 am
L1 is parallel to L3;

Both are required to answer. (that is C, right?)

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by bryan88 » Tue Apr 03, 2012 11:01 am
Question asks for relation between L1 and L3.

A) L3 not mentioned( Insufficient)
B) L1 not mentioned( Insufficient)

combine to find L1//L3

C.

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by Bill@VeritasPrep » Tue Apr 03, 2012 11:48 am
bryan88 wrote:Question asks for relation between L1 and L3.

A) L3 not mentioned( Insufficient)
B) L1 not mentioned( Insufficient)

combine to find L1//L3

C.
Exactly. To answer, we need to know about the relationship between L1 and L3. Neither statement contains information about both lines, so we need to put them together to be able to answer.
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by Anurag@Gurome » Tue Apr 03, 2012 9:18 pm
Md.Nazrul Islam wrote:If L1,L2,L3 are lines in a plane is L1 perpendicular to L3?

1) L1 is perpendicular to L2 .

2)L2 is perpendicular to L3.
(1) L1 is perpendicular to L2.

Image
The figure clearly shows that L1 may or may not be perpendicular to L3; NOT sufficient.

(2) L2 is perpendicular to L3.

Image

The figure clearly shows that L1 may or may not be perpendicular to L3; NOT sufficient.

Combining (1) and (2), L1 is perpendicular to L2 and L2 is perpendicular to L3.

Image


So, combining we can answer the question; SUFFICIENT.

The correct answer is C.
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