# binomial probability formula

Binomial Probability Formula

A probabilityformula for Bernoulli trials. The probability of achieving exactly k successes in n trials is shown below.

 Formula: n = number of trialsk = number of successesn – k = number of failuresp = probability of success in one trialq = 1 – p = probability of failure in one trial Example: You are taking a 10 question multiple choice test. If each question has four choices and you guess on each question, what is the probability of getting exactly 7 questions correct?n = 10k = 7n – k = 3p = 0.25 = probability of guessing the correct answer on a questionq = 0.75 = probability of guessing the wrong answer on a question