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The relation linking arrangements and selections of r objects from n is nPr equals:
AnCr plus r factorial
BnCr minus r factorial
CnCr over r factorial
DnCr times r factorial
Answer & Solution
Correct answer: D. nCr times r factorial
1. First choose the r objects.
2. Then arrange them in r factorial ways.
3. So nPr is nCr times r factorial.
_Source: NCERT Class 11 Mathematics, Chapter 7, Permutations and Combinations._
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