Combinations function

To use this function, choose Calc > Calculator.

Combinations are a selection of objects from a group, when the order of the selection does not matter. For example, the combinations of the letters abcd taken three at a time are abc, abd, acd, bcd. The subgroups abc and bca are considered the same combination, because order does not matter.

Use the Combinations function to calculate the number of combinations of n items chosen k at a time. This function is used in the formula to calculate the probability of observing k events (successes) in n trials in an experiment with only two outcomes (a binomial experiment).

Syntax

COMBINATIONS(number of items, number to choose)

Specify a number or column for the number of items and the number to choose. The number of items must be greater than or equal to 1, and the number to choose must be greater than or equal to 0.

Example

A researcher conducts a study with three people, but there are ten people willing to participate. The researcher wants to know how many combinations of three people can be chosen for the study.

Calculator expression Result
COMBINATIONS(10,3) 120