Introduction to Probability · 免费预览

计数、乘法法则与二项式系数

乘法法则、有序与无序抽取的抽样表,以及二项式系数及其恒等式。

1. The multiplication rule

The multiplication rule

2. The sampling table

The sampling table

3. Working with binomial coefficients

Working with binomial coefficients

4. Choosing the right scheme

From a standard 52-card deck you draw 5 cards and keep them, caring only about which cards end up in your hand. Which count is correct?

5. Pascal recursion by story

The identity Binomial(n, k) = Binomial(n-1, k) + Binomial(n-1, k-1) has a direct committee story. What split does it use?

6. Counting passwords

A password consists of 4 symbols, each a lowercase letter a-z or a digit 0-9. Repeats are allowed. How many passwords are possible? Enter the integer.

7. Gold medals

In an 8-runner race, gold, silver and bronze go to distinct runners, in order of finish. How many medal outcomes are possible? Enter the integer.

8. A bookshelf identity

Using the binomial theorem with x = 1 and y = 2, the sum of Binomial(5, k) times 2 to the k, for k from 0 to 5, equals (1 + 2)^5. What is that value? Enter the integer.

9. In your own words

In your own words, state the most important definition, theorem or method of this lesson and explain what it says.

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