COMBIN

The COMBIN function returns the number of combinations for a given number of items. A combination is a group of items where order does not matter. The COMBIN function does not allow repetitions. To count combinations that allow repetitions, use the COMBINA function. To count permutations (combinations where order does matter) see the PERMUT function. A good real-world example is a committee: choosing 3 people from a group of 10 is a combination because the order of the names does not matter, and no person can be chosen twice. For a full explanation, see Combinations and permutations in Excel. To use COMBIN, specify the total number of items and "number_chosen", which represents the number of items in each combination. For example, to calculate the number of 3-number combinations, you can u