60 degree angle in quadrilateral

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60 degree angle in quadrilateral

by Gmat09_5ALL » Sun Sep 13, 2009 7:29 am
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 - C
Source: — Data Sufficiency |

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by Ian Stewart » Sun Sep 13, 2009 9:20 am
Even with both Statements, you could have angles 60-90-90-120, or you could have 45-90-90-135 (notice in each case, you have two right angles, and you have one angle which is twice another), so the answer is E.
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