Processing math: 100%

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Chapter1Counting

One of the first things you learn in mathematics is how to count. Now we want to count large collections of things quickly and precisely. For example:

In a group of 10 people, if everyone shakes hands with everyone else exactly once, how many handshakes took place?
How many ways can you distribute $10$ girl scout cookies to $7$ boy scouts?
How many anagrams are there of “anagram”?

Before tackling questions like these, let's look at the basics of counting.