हिंदी

In the permutations of n things, r taken together, the number of permutations in which m particular things occur together is PPn-mPr-m×rPm.

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प्रश्न

In the permutations of n things, r taken together, the number of permutations in which m particular things occur together is `""^(n - m)"P"_(r - m) xx ""^r"P"_m`.

विकल्प

  • True

  • False

MCQ
सत्य या असत्य
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उत्तर

This statement is False.

Explanation:

Arrangement of n things, r taken at a time in which m things occur together.

So, number of object excluding m object = (r – m)

Here, we first arrange (r – m + 1) object

∴ Number of arrangements = (r – m + 1)!

m objects can be arranged in m! ways

So, the required number of arrangements = (r – m + 1)! × m!

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

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
अध्याय 7 Permutations and Combinations
Exercise | Q 53 | पृष्ठ १२६

वीडियो ट्यूटोरियलVIEW ALL [1]

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