BINOM.INV function

The BINOM.INV function in Excel returns the smallest value for which the cumulative binomial distribution is greater than or equal to a criterion value. It’s used to find the inverse of the binomial distribution, i.e., to find the number of successes associated with a given probability.

Syntax:

BINOM.INV(trials, probability_s, alpha)

Arguments:

• trials: The number of independent trials (integer).
• probability_s: The probability of success on each trial (decimal between 0 and 1).
• alpha: The criterion probability (also between 0 and 1). This is the cumulative probability threshold that you’re trying to reach or exceed.

Example:

If you perform 10 trials with a probability of success of 0.3 per trial and want to find the smallest number of successes for which the cumulative probability is at least 0.7, you would use:

=BINOM.INV(10, 0.3, 0.7)

This would return the smallest number of successes (from 0 to 10) such that the cumulative binomial probability is greater than or equal to 0.7.