# 7: Miscellaneous Topics

- Page ID
- 8986

- 7.1: Using Summation Notation
- When we have an expression with many numbers added to each other, there is a notation that makes the formulas easier to write down.

- 7.2: Rounding and Scientific Notation
- In this section, we will go over how to round decimals to the nearest whole number, nearest tenth, nearest hundredth, etc. In most statistics applications that you will encounter, the numbers will not come out evenly, and you will need to round the decimal.

- 7.4: Factorials and Combination Notation
- When we need to compute probabilities, we often need to multiple descending numbers. For example, if there is a deck of 52 cards and we want to pick five of them without replacement, then there are 52 choices for the first pick, 51 choices for the second pick since one card has already been picked, 50 choices for the third, 49 choices for the fourth, and 48 for the fifth.