http://www.ck12.org Chapter 2. Conditional Probability
2.6 Combination Problems
Here you’ll learn how to use a Texas Instruments calculator to solve combination problems.
There are 100 senators in the United States Senate. If they must each enter the entrance to the Senate one-by-one,
how many possible ways can this happen? Can you see why a calculator or some other process might be useful to
solve this combination problem? Check out an interesting solution at http://puzzles.nigelcoldwell.co.uk/nineteen.
htm.
Watch This
First watch this video to learn about calculating combinations with calculators.
MEDIA
Click image to the left for more content.CK-12 Foundation: Chapter2CombinationProblemsA
Then watch this video to see some examples.
MEDIA
Click image to the left for more content.CK-12 Foundation: Chapter2CombinationProblemsB
Guidance
To calculate combinations (nCr) on the TI calculator, first enter thenvalue, and then press
MATH. You should see menus across the top of the screen. You want the fourth menu: PRB (arrow right 3 times). The
PRB menu should appear as follows: