The randBin( Command

Command Summary

Generates a random number with the binomial distribution.

Command Syntax

randBin(n,p,# simulations)

Menu Location


  1. MATH to access the math menu.
  2. LEFT to access the PRB submenu.
  3. 7 to select randBin(, or use arrows.

Calculator Compatibility


Token Size

2 bytes

randBin(n,p) generates a pseudorandom integer between 0 and n inclusive according to the binomial distribution B(n,p) - that is, n trials of an event with probability of success p are performed, and the number of successes is returned. randBin(n,p,simulations) performs the above calculation simulations times, and returns a list of the results. The expected (average) result is n*p.

n should be an integer greater than or equal to 1, while p should be a real number between 0 and 1 inclusive.

seed→rand affects the output of randBin(

     {3 3 2 4 3 2 2 2 4 3}


The value of randBin( for a given seed can be expressed in terms of rand:


This is identical to the output of randBin( in the sense that for the same seed, both expressions will generate the same random numbers.

Error Conditions

  • ERR:DOMAIN is triggered if the probability is not on the interval from 0 to 1.

Related Commands


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