C and P

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Number of quadrilaterals which can be constructed by joining the vertices of a convex polygon of 20 sides if none of the side of the polygon is alsoi the side of the quadrilateral is:

#Mathematics #Algebra

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8 Answers

49

Subhomoy Bakshi ·2011-03-13 04:34:06

it is like there are 20 chairs around a table..

find number of ways of seating 4 people on these chairs such that none sits besidee another! :)

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1

seoni ·2011-03-13 07:05:48

20C9?

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1

Neeraj Das ·2011-03-13 08:02:06

170 ?

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1

Vinay Arya ·2011-03-13 20:06:03

All the answers are wron g.The answer I have is 5.¹⁵C₃.

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71

Vivek @ Born this Way ·2011-03-14 02:29:03

Any reasoning for your answer? By the way, other answers are really wrong

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1

Neeraj Das ·2011-03-15 04:03:40

Pls show the procedure......

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1

Vinay Arya ·2011-03-16 03:58:17

If you want to give your answer then please write the procedure.

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Vinay Arya ·2011-03-16 03:59:08

Vivek
How can I have any reasoning for my answer as I am the asker?

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Your Answer

Basic Integral Calculus Operators Symbols Matrix Cases

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° ∂ ∞ α β γ δ θ λ μ ν ξ π ρ σ φ ω ε ƒ κ τ υ Γ Δ Λ Σ Π Ω