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

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In a certain circle there are 10. What is the number of the triangles connecting 3 points of the 10 points?

A. 80
B. 96
C. 108
D. 120
E. 132

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by regor60 » Thu Feb 18, 2016 6:49 am
Max@Math Revolution wrote:In a certain circle there are 10. What is the number of the triangles connecting 3 points of the 10 points?

A. 80
B. 96
C. 108
D. 120
E. 132

* A solution will be posted in two days.
I've lost count of how many of your posts lack complete information, please try harder

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by Max@Math Revolution » Sat Feb 20, 2016 10:27 pm
In a certain circle there are 10. What is the number of the triangles connecting 3 points of the 10 points?

A. 80
B. 96
C. 108
D. 120
E. 132


--> If you connect 3 points out of 10, they make a circle. So, 10C3=10*9*8/3*2*1=120. Therefore, the answer is D.