If n is a number of items and we need to choose r items out of the n without placing them back into the set then this can be done in nPr ways. This is the number of permutations of
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Could you be a little more descriptive? Thank you for using
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The combination formula is usually written as. n. C. r. representing the number of combinations of r objects at a time taken from n. n. C. r. = n!/[r!nr) The permutation formula
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1. Define a combination. A combination is the number of ways that objects can be arranged, in which order of the objects does not matter. This means that AB is not a different way
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