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Binom dist

BINOM.DIST Function

The BINOM.DIST function in Excel is used to calculate the binomial probability distribution for a given number of successes in a set of independent trials. It is particularly useful for statistical analysis when dealing with experiments or phenomena with binary outcomes (e.g., success/failure, true/false).

Key Features of BINOM.DIST:

  • Computes the probability of getting a specified number of successes over a defined number of independent trials.
  • Allows for calculating either exact probabilities or cumulative probabilities up to a certain number of successes.
  • Ideal for scenarios modeled by the binomial distribution, such as coin flips, quality testing, or event outcomes with fixed probabilities.

Syntax:

BINOM.DIST(number_s, trials, probability_s, cumulative)
  • number_s: The number of successes for which the probability is calculated. Must be a non-negative integer.
  • trials: The total number of independent trials. Must be a positive integer.
  • probability_s: The probability of success for an individual trial. Must be between 0 and 1.
  • cumulative: A logical value (TRUE or FALSE) that specifies whether to compute cumulative probabilities:
    • TRUE: Calculates the probability of getting up to and including number_s successes.
    • FALSE: Calculates the probability of getting exactly number_s successes.

Examples:

  1. =BINOM.DIST(3, 10, 0.5, FALSE)
    Calculates the probability of exactly 3 successes in 10 trials, with a success probability of 0.5. Result: 0.117188.

  2. =BINOM.DIST(2, 5, 0.7, TRUE)
    Computes the cumulative probability of having at most 2 successes in 5 trials, where the success probability is 0.7. Result: 0.16308.

  3. =BINOM.DIST(4, 8, 0.25, FALSE)
    Calculates the exact probability of getting exactly 4 successes in 8 trials, with a success probability of 0.25. Result: 0.033203.

Notes:

  • If any input arguments fall outside their valid ranges (number_s < 0, trials < 1, or probability_s not between 0 and 1), the function returns an error (#NUM! or #VALUE!).
  • The trials are assumed to be independent, and the probability of success remains constant throughout all trials.
  • In the case of cumulative probabilities (cumulative = TRUE), the function sums the probabilities of all outcomes up to and including number_s successes.

Tip: Use BINOM.DIST for evaluating scenarios where the binomial distribution applies, such as assessing product reliability, testing proportions, or modeling binary experiments.