In a small chess tournament, 20 matches were played. find out how many people were involved if it is known that each participant played 2 games with every other participant in the tournament.

Step-by-step explanation:

Given :  

20 matches were played in a small chess tournament.

Each participant played 2 games with every other participant in the tournament.

To Find : how many people were involved?

Solution :

Let no. of players involved be n

Since we know that for every match there should be two players out of n

So, number of ways they can play :

We  are also given that  each participant played 2 games with every other participant.

So, total no. of games played  =

Since we are given that total no. games played = 20

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⇒

⇒  --(a)

Formula of combination:

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So, solving (a) further using formula

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⇒

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⇒

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⇒

⇒

⇒

⇒

⇒ n = 5 , n =-4

Neglect the negative value since no. of players cannot be negative.

Thus no. of player involved is 5.

just find the gcf and solve the gcf's until you get each answer i have a really good feeling somethings missing xd (like the dimensions of the fence) *cough *cough *hint *hint

step-by-step explanation: