What is a binomial distribution?

Updated May 17, 2026

Short answer

Binomial distribution models number of successes in n independent Bernoulli trials.

Deep explanation

It is defined as P(X=k)=C(n,k)p^k(1-p)^(n-k). It models repeated independent binary experiments with fixed probability.

Real-world example

Number of heads in 10 coin flips.

Common mistakes

  • Assuming trials can have changing probability.

Follow-up questions

  • What are binomial assumptions?
  • What is expectation of binomial?

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