मराठी

In a football championship, 153 matches were played, Every two teams played one match with each other. The number of teams, participating in the championship is ______. - Mathematics

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प्रश्न

In a football championship, 153 matches were played, Every two teams played one match with each other. The number of teams, participating in the championship is ______.

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उत्तर

In a football championship, 153 matches were played, Every two teams played one match with each other. The number of teams, participating in the championship is 18.

Explanation:

Let the number of participating teams be n

Given that every two teams played one match with each other.

∴ Total number of matches played = nC2

So nC2 = 153

⇒ `(n(n - 1))/2` = 153

⇒ n2 – n = 306

⇒ n2 – n – 306 = 0

⇒ n2 – 18n + 17n – 306 = 0

⇒ n(n – 18) + 17(n – 18) = 0

⇒ (n – 18)(n + 17) = 0

⇒ n – 18 = 0 and n + 17 = 0

⇒ n = 18, n ≠ – 17

Hence, the value of the filler is 18.

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पाठ 7: Permutations and Combinations - Exercise [पृष्ठ १२६]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
पाठ 7 Permutations and Combinations
Exercise | Q 47 | पृष्ठ १२६

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