Angles of a Quad

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Angles of a Quad

by nervesofsteel » Wed Jul 08, 2009 2:15 pm
Is the measure of one of the interior angles of quadrilateral ABCD equal to 60 degrees?
(1) Two of the interior angles of ABCD are right angles.
(2) The degree measure of angle ABC is twice the degree measure of angle BCD.
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is
sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.

IMO E
but OA C

The angles can be : 90,90,45,135
or
90,90,60,120
Source: — Data Sufficiency |

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Re: Angles of a Quad

by ssmiles08 » Wed Jul 08, 2009 4:47 pm
nervesofsteel wrote:
The angles can be : 90,90,45,135
or
90,90,60,120
45 and 135 do not satisfy requirement 2. 135 is not twice the size of 45.

the only angles that agree with the two requirements are 90, 90, 60 and 120.

180 + 3x = 360.

x = 60
2x = 120.

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by nervesofsteel » Thu Jul 09, 2009 12:49 am
yes but 90 is double of 45...

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by ssmiles08 » Thu Jul 09, 2009 2:59 am
oh you are right...I didn't see it that way...I agree with you then IMO E.

maybe we are missing something??

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Re: Angles of a Quad

by clar » Thu Jul 09, 2009 3:42 am
nervesofsteel wrote:Is the measure of one of the interior angles of quadrilateral ABCD equal to 60 degrees?
(1) Two of the interior angles of ABCD are right angles.
(2) The degree measure of angle ABC is twice the degree measure of angle BCD.
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is
sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.

IMO E
but OA C

The angles can be : 90,90,45,135
or

90, 90, 45 , 135 is not a possible case becoz it is already mentioned in the question stem that one of the interior angles is 60.

hope that helps.

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Re: Angles of a Quad

by ssmiles08 » Thu Jul 09, 2009 11:02 am
clar wrote:
90, 90, 45 , 135 is not a possible case becoz it is already mentioned in the question stem that one of the interior angles is 60.

hope that helps.
I don't see it mentioned in the question stem. It is asking IS one of the angles is 60 degrees?

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by clar » Thu Jul 09, 2009 10:16 pm
yep, you are right . i misread the question!

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by gmat740 » Thu Jul 09, 2009 11:26 pm
Guys,I did this question a long time back, but I believe the answer was E

You must have a error in OA

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by nervesofsteel » Thu Jul 09, 2009 11:27 pm
Thanks guys...

May be the OA is wrong...

Any further comments are most welcome...