मराठी

From Among the 36 Teachers in a School, One Principal and One Vice-principal Are to Be Appointed. in How Many Ways Can this Be Done?

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प्रश्न

From among the 36 teachers in a school, one principal and one vice-principal are to be appointed. In how many ways can this be done?

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उत्तर

Here, we need to permute 2 teachers out of the 36 available teachers.
It can also be understood as the arrangement of 36 teachers, taken two at a time.
∴ Required number of ways = 36P2

\[= \frac{36!}{\left( 36 - 2 \right)!}\]
\[ = \frac{36!}{34!}\]
\[ = \frac{36 \times 35 \times 34!}{34!}\]
\[ = 36 \times 35 \]
\[ = 1260\]

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Factorial N (N!) Permutations and Combinations
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 16: Permutations - Exercise 16.3 [पृष्ठ २८]

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आर.डी. शर्मा Mathematics [English] Class 11
पाठ 16 Permutations
Exercise 16.3 | Q 16 | पृष्ठ २८

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