# Combinations

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More Lessons for Algebra II
Math Worksheets

Videos, worksheets, games and activities to help Algebra II students learn about combinations.

What is a combination?
A combination is a grouping or subset of items. For a combination, the order does not matters.
C(n,r) represents the number of combinations of n items taken r at a time.

The following figure gives the formula to find the number of combinations of n items taken r at a time. Scroll down the page for more examples and solutions.

In this lesson, you will learn
How to evaluate a combination?
How to use combinations to solve problems?

This video introduces combinations and explains how to evaluate combinations as well as solve counting problems using combinations.

Probability using Combinations
Probability of getting exactly 3 heads in 8 flips of a fair coin.
Probability and Combinations (part 2)
Math Combinations
Students learn that a combination is an arrangement of objects in which the order is not important.

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