Binomial Probability

 

Finding Individual Probabilities (P(X=x))

  1. Let’s suppose that I am trying to find the probability that a X=5 when you have a Binomial (20, .5)
  2. First enter the number of Successes (5) into the first row of C1.
  3. Go to Calc, Probability Distribution,  Binomial.
  4. The screen below will appear.

  1. Notice that I have entered 20 for the Number of trials and .5 for the probability of success. I have also entered the input column as C1.
  2. If you do not enter a column into the Optional Storage blank, Minitab will display the answer in the session window.

 

Probability Density Function

 

Binomial with n = 20 and p = 0.5

 

x  P( X = x )

5   0.0147858

 

 

Finding the Cumulative Probability (P(X<=x))

  1. Let’s suppose that I am trying to find the probability that a X is less than or equal to 5 when you have a Binomial (20, .5)
  2. First enter the number of Successes into the first row of C1.
  3. Go to Calc, Probability Distribution, Binomial.
  4. The screen below will appear.

  1. Notice that I have entered 20 for the Number of trials and .5 for the probability of success. I have also entered C1 for the input column.
  2. If you do not enter a column into the Optional Storage blank, Minitab will display the answer in the session window.

 

Cumulative Distribution Function

 

Binomial with n = 20 and p = 0.5

 

x  P( X <= x )

5    0.0206947