# TI-84 Plus Faq

Alex November 20, 2019

TI-84 Plus is one of the best graphing calculators on the market today.

Contents

## How to find … questions

### How to find standard deviation on TI-84 plus?

In statistics, the standard deviation (SD, also represented by the lower case Greek letter sigma σ or the Latin letter s) is a measure that is used to quantify the amount of variation or dispersion of a set of data values. A low standard deviation indicates that the data points tend to be close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the data points are spread out over a wider range of values.

Source: https://en.wikipedia.org/wiki/Standard_deviation

Standard Deviation:

#### Step 1. Press STAT Button and select “1: Edit” in menu.

In this menu, you can enter each value in the dataset. You will see the table with columns labeled from L1 to L6. If you have any data in this list you need to clear it before continue. Go up to L1 and push “Clear” button and then “Enter”.

#### Step 2. Enter your data

Enter your numbers and press enter after each of them.

#### Step 5. Results

Here is we see several different values.
You need Sx which is mean Standard Deviation.

### How to do fractions on a TI-84 Plus

Simple Fraction

#### Step 1. Click “Alpha”=>”F1”. Now you are in Fraction menu. Select 1 option and press “Enter”.

You can enter numerator to enter denumenator press “down” button and enter it. When finish press “Right” button. Now you can enter +/- etc. To enter new fraction repeat Step 1.

#### Step 2. To calculate fraction just press “Enter”

Fraction with mix number

#### Step 1. Click “Alpha”=>”F1”. Now you are in Fraction menu. Select 1 option and press “Enter”.

You can enter numerator to enter denumenator press “down” button and enter it. When finish press “Right” button. Now you can enter +/- etc. To enter new fraction repeat Step 1.

#### Step 3. Press “Enter” button to get result.

Here we have improper fraction. Let’s convert it to Mix Fraction in next step..

### How to find correlation coefficient

Correlation Coefficient

#### Step 1. Importan. Turn On Diagnostic.

You need make it just once, so if you enable it before just skip this step. If you doesn’t do it you won’t see R and R squared when do your work. To turn it ot Click “2nd” => “0” => Diagnstic On. => “Enter” => “Enter”

#### Step 2. Enter your Data

Click “Stat” => 1. Edit => “Enter” and enter your data.

#### Step 3. Calculate it.

Click “Stat” => Right to Calculate => 4. LinReg (ax+b). Then click “Calculate”.

Absolut Value