In a certain circle there are 10 points. What is the number

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In a certain circle there are 10 points. What is the number of the hexagons connecting 6 points of the 10 points?

A. 180
B. 196
C. 210
D. 240
E. 256


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by Max@Math Revolution » Thu Apr 07, 2016 5:06 am
In a certain circle there are 10 points. What is the number of the hexagons connecting 6 points of the 10 points?

A. 180
B. 196
C. 210
D. 240
E. 256


-> 10C6=10C4=(10)(9)(8)(7)/4!=210.
Thus, the answer is C.

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by DavidG@VeritasPrep » Sat Apr 16, 2016 7:50 am
See here for another good shape/combination question: https://www.beatthegmat.com/gmat-prep-qu ... 69317.html
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