How to Use BinomCDF
Learn what BinomCDF means and how to use the cumulative binomial distribution function for at-most, at-least and range probabilities.
What is BinomCDF?
BinomCDF means binomial cumulative distribution function. It gives the probability of getting a specified number of successes or fewer in a binomial experiment.
For example, binomcdf(10, 0.5, 3) asks for the probability of 3 or fewer successes in 10 trials when the probability of success on each trial is 0.5.
How to use BinomCDF
- Identify n, the number of trials.
- Identify p, the probability of success on each trial.
- Identify x, the largest number of successes included.
- Enter the values in your calculator's BinomCDF function.
How to calculate at least
BinomCDF naturally calculates a left cumulative probability. For an at-least question, use the complement.
For example, P(X ≥ 4) = 1 − binomcdf(n, p, 3).
How to calculate a range with BinomCDF
So a calculator expression can use the cumulative probability through b minus the cumulative probability through a − 1.
BinomPDF vs BinomCDF
BinomPDF is used for an exact number of successes, P(X = x). BinomCDF is used for a cumulative probability, P(X ≤ x).
Use our online calculator
Our Binomial Distribution Calculator lets you choose P(X = x), P(X ≤ x), P(X ≥ x), less than, greater than and range probabilities without entering calculator-specific commands.