Geometric Distribution Calculator

Find P(first success on trial k).

P(X = k) (%) 12.8

Expected trials 5

Formula: P = (1−p)^(k−1) · p

Step-by-step with your numbers:

1. Values used:

2. Success probability = 0.2

3. Trial of first success (k) = 3

5. P(X = k) = 12.8%

6. Expected trials = 5

Did we solve your problem today?

The geometric distribution gives the probability the first success comes on trial k.

The math behind it

P(X=k) = (1−p)^(k−1) × p. Expected number of trials = 1 ÷ p.

p 0.2, k 3 → 12.8% (expected 5 trials).

Use?

Trials until the first success, like a sale after cold calls.