Let’s walk through how to calculate the probability of 1 out of 3 crimes being solved in the FBI Crime Survey example.

Recall in that example, \(n=3\), \(p=0.2\).

Using Minitab, calculate \(P(X=1)\):

1. From the Minitab menu select Calc > Probability Distributions > Binomial
2. A dialog box (below) will appear. Enter 3 into the Number of Trials box and 0.2 into the Event Probability box.
3. Choose Probability .
4. Choose the Input Constant Box and enter 1.
5. Choose OK .

The result should be the same probability of 0.384 we found by hand.

Suppose we want to find \(P(X\le 2)\). We can use Minitab to find this cumulative probability.

1. From the Minitab menu select Calc > Probability Distributions > Binomial
2. Enter in 3 and 0.2 as above.
3. Choose Cumulative Probability .
4. Choose Input Constant and enter 2.
5. Choose OK .

The result should be \(P(X\le 2)=0.992\).