What is the Geometric Distribution?

It models the number of trials needed to get the first success in a sequence of independent Bernoulli trials (success/failure).

What does 'p' represent?

The probability of success on a single trial (e.g., 0.5 for a coin flip).

Calculating the probability that you make your first sale on the 5th call, given a 10% conversion rate.

Calculate probability of needing k trials for the first success.

Probability of Success (p)

0 < p <= 1

Number of Trials (k)

Target trial for first success

P(X = 3)

P(X ≤ 3) = 0

Expected Trials (Mean)

Variance

Formulas

PMF P(X=k)

CDF P(X\le k)

Mean

Variance

Frequently Asked Questions

How to Use

What it calculates

This geometric solves mathematical and statistical problems using standard formulas. Calculate trials until first success.

When to use it

Use for homework, data analysis, exam prep, or quick verification of manual calculations.

Example

Adjust the inputs above to model your specific scenario with the Geometric.

Explore More

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