Combinations and permutations measure the number of ways items from a set can be grouped. Combinations do not count different orders as different groupings. For example, for the purposes of counting combinations, a selection of chocolate, vanilla and strawberry would be the same thing as a selection of chocolate, strawberry and vanilla. However, since order does matter for permutations, those two would be counted separately when totaling the number of permutations. To convert, you need to know the factorial function, which you get by multiplying the number by itself and every lower positive integer. For example, four factorial would be four times three times two times one.
Instructions
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1
Count the number of items you put into each combination. For example, if you have the number of combinations for ice cream bowls in which you put three flavors, you would count three items.
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2
Calculate the factorial of the number of items. For this example, calculate three factorial, which equals three times two times one (i.e., six).
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3
Multiply the number of combinations by the result to find the number of permutations. For example, if you have 120 combinations, multiply 120 by six to get 720 permutations.