## How to Calculate TI 83 Permutations and TI 83 Combinations

While our free, online Combinations Calculator and Permutations Calculator can solve your combinations and permutation problems in seconds, you can’t take it to a test. A permutation problem is one in which a certain number of items are selected in order and that order matters (for example, picking 1st, 2nd, and 3rd prize winners in a raffle). With combinations, the order doesn’t matter (for example, picking 3 people for a work party). While doing this by hand is cumbersome (the equation you use involves factorials like n! and r!), the calculator can figure it out at the press of a button. Plus, you can take the TI 83 to the test!

## TI 83 Combinations (n! / (n – r!) r!)

Sample problem: If there are 5 people, Barb, Sue, Jan, Jim, and Rob, and only three will be chosen for the new Parent Teacher Association, how many combinations are possible for the committee?

Step 1: Enter the number of items on the home screen (the main input area) that you have to choose from. In the above example, you have 5 people, so press .

Step 2:Math button.

Step 3: Use the right arrow key to tab across to “PRB”.

Step 4: Press . This inserts nCr onto the home screen.

Step 5: Enter the number of items you want to choose. In the above example, you want to choose 3, so press .

Step 6: Press . The calculator will return the result: 10.

## TI 83 Permutations (n! / (n – r!))

Sample problem: If there are 5 people, Barb, Sue, Jan, Jim, and Rob, and three will be chosen for the new Parent Teacher Association. The first person picked will be the president, then the vice president, then the secretary. How many permutations are possible for the committee?

Step 1: Enter the number of items on the home screen (the main input area) that you have to choose from. In the above example, you have 5 people, so press .

Step 2: Press the button.

Step 3: Use the right arrow key to tab across to “PRB”.

Step 4: Press . This inserts nPr onto the home screen.

Step 5: Enter the number of items you want to choose. In the above example, you want to choose 3, so press .

Step 6: Press . The calculator will return the result: 60.