## Permutations FunctionMath Probability Class

```Public Function Permutations( _
ByVal vNumber As Variant _
, ByVal vChosen As Variant _
) As Variant```

### Permutation of N things taken C at a time.

Summary: The number of ways that C things can be chosen from N things when the order in which they are chosen matters. To calculate how many possible first, second, and third place winners there are in a field of 10 people, use Permutations(10, 3).
Examples:
```    Permutations(1, 1) = 1
Permutations(2, 1) = 2
Permutations(2, 2) = 2
Permutations(4, 1) = 4
Permutations(4, 2) = 12
Permutations(4, 3) = 24
Permutations(4, 4) = 24
Permutations(5, 4) = 120
Permutations(5, 5) = 120
Permutations(21, 9) = 106661318400
IsNull(Permutations(9, 21)) = True```
See also:
```    Combinations Function
CombinationsWithRepetitions Function
Factorial Function
PERMUT Function (Microsoft Excel)```
vNumber: The number of unique items from which permutations can be constructed. Function returns Null if vNumber is Null, cannot be interpreted as a number, is less than or equal to zero (<=0), or is less than vChosen. vNumber will be rounded down to the nearest integer.
vChosen: The number of items which are to be combined each time some are selected. Function returns Null if vChosen is Null, cannot be interpreted as a number, or is less than zero (<0). vChosen will be rounded down to the nearest integer.
Note: Function will return Null instead of generating an error if any of its calculations cause Overflow or other types of errors.
Definition:
`    Factorial(N) / Factorial(N - C)`
v1.5 Pro Note: The argument names and the implementation of this function has changed.

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