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Which relation connects the number of permutations and the number of combinations of n things taken r at a time?
AnCr plus r!
BnCr over r!
CnCr times r!
DnCr minus r!
Answer & Solution
Correct answer: C. nCr times r!
1. Each single combination lists r objects with no order attached.
2. Those r objects can be rearranged among themselves in r factorial ways.
3. So nPr equals nCr multiplied by r factorial.
_Source: NCERT Class 11 Mathematics, Ch 6 'Permutations and Combinations'_
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