Tricky question help me to solve it........

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Tricky question help me to solve it........

by pzazz12 » Mon Oct 04, 2010 4:21 am
In a class of 40 students, 12 enrolled for both English and German. 22 enrolled for German. If the students of the class enrolled for at least one of the two subjects, then how many students enrolled for only English and not German?

A. 30
B. 10
C. 18
D. 28
E. 32
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by sumit.sinha » Mon Oct 04, 2010 4:33 am
pzazz12 wrote:In a class of 40 students, 12 enrolled for both English and German. 22 enrolled for German. If the students of the class enrolled for at least one of the two subjects, then how many students enrolled for only English and not German?

A. 30
B. 10
C. 18
D. 28
E. 32
Using double-axis matrix, answer = C
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by Rahul@gurome » Mon Oct 04, 2010 7:31 am
Answer choices are not in correct GMAT order.
Let E = students who enrolled for English
G = students who enrolled for German
Students who enrolled for both E and G = 12
So, 40 = E + 22 - 12
E = 30, which also includes the students who enrolled for German also.

Therefore, students who enrolled for only English and not German = 30 - 12 = 18

[spoiler]The correct answer is (C).[/spoiler]
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by Yanat » Mon Oct 04, 2010 8:32 am
Using the Simple Venn Diagram concepts

40 = x+12+10 and so x = 18