How many triangles can be formed in a decagon? - Noon Academy

How many triangles can be formed in a decagon?

Rs aggarwal Maths CBSE Class 11 Chapter 9 Exercise 9B

How many triangles can be formed in a decagon?

Answer : Total number of sides in a decagon = 10 We know that number of vertices in triangle = 3

So, out of 10 vertices we have to choose 3 vertices. Therefore,

Total number of triangles in a decagon

Total number of triangles = 120

i

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