ABCDE is a regular pentagon with F at its center. How many different triangles can be formed by joining 3 of the points A, B, C, D, E and F?
10
15
20
25
30
10
15
20
25
30
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Is the OA 6c3 = 20??pradeepkaushal9518 wrote:ABCDE is a regular pentagon with F at its center. How many different triangles can be formed by joining 3 of the points A, B, C, D, E and F?
I still believe answer should be only 6c3 = 20. Because, any 3 points can form the triangle..pradeepkaushal9518 wrote:no kvcpk 20 is not the answer.i dont know the method to solve it
Hi,shankysainik wrote:Is it 15?
5C3 = 10 (For any 3 points among A,B,C,D,E)
and 5 for the number of triangles possible using the centre F)
Please let me know if this is right!
I am with kvcpk, we have 6 vertices with no three vertices in the same line hence we can have 6C3 triangles.......kvcpk wrote:Hi,shankysainik wrote:Is it 15?
5C3 = 10 (For any 3 points among A,B,C,D,E)
and 5 for the number of triangles possible using the centre F)
Please let me know if this is right!
ABCDE is a regular pentagon.. So F will not fall in line with any lines drawn between two sides. Hence F can form a triangle with any of the two vertices...
You missed out the triangles ACF, ADF,etc..
What you say??
No Problem... Happy to see that what I thought was rightpradeepkaushal9518 wrote:sorry kvcpk answer is 20 only i have choosen 15 which was wrong.
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