Education Technology

# Knowledge Base

## Solution 11921: Calculating Hypergeometric Probability Distributions on the TI-83 Plus and TI-84 Plus.

### How do I calculate a hypergeometric probability distribution on the TI-83 Plus and TI-84 Plus?

There is no pre-defined function in the calculator that will find the statistical values for a hypergeometric probability distribution. However, users can enter the formula to find the results for this type of distribution into the calculator.  The instructions below describe how to find P(1) of a hypergeometric probability distribution.

Example: Find P(1) when N = 12, n = 4, and k = 3

Since P(x) = {C(k, x) × C(N-k, n-x)} ÷ C(N, n)

With substitution, P(1) = {C(3, 1) × C(12-3, 4-1)} ÷ C(12, 4)

So the values should be entered using the following steps:
• Input [(] [(] [3]
• Press [MATH], then press the right arrow key 3 times to select the PRB menu
• Press [3] to select 3:nCr
• Input [1] [)] [(] [9]
• Press [MATH], then press the right arrow key 3 times to select the PRB menu
• Press [3] to select 3:nCr
• Input [3] [)] [)] [÷] [1] [2]
• Press [MATH], then press the right arrow key 3 times to select the PRB menu
• Press [3] to select 3:nCr
• Input [4], then press [ENTER]

The answer of .5090909091 should be displayed.

Please see the TI-83 Plus and TI-84 Plus guidebooks for additional information.