How to Find Standard Deviation on a TI-84 Calculator

Introduction

Standard deviation measures how spread out a data set is. On the TI-84, you usually enter values into a list and run 1-Var Stats.

Step-by-step instructions

1. Press STAT.
2. Choose Edit.
3. Enter your data values in L1.
4. Press STAT again.
5. Move to CALC.
6. Choose 1-Var Stats.
7. Enter L1 if needed, then press ENTER.
8. Read Sx for sample standard deviation or σx for population standard deviation.

Practical example

For the data set 4, 6, 8, 10, enter each value in L1. Run 1-Var Stats. Use Sx when your values are a sample and σx when they represent the full population.

Common mistakes

• Reading σx when the homework asks for sample standard deviation.
• Leaving old values in L1.
• Entering commas incorrectly instead of placing values in list rows.
• Forgetting to check whether the problem uses a sample or population.

FAQ

What is the difference between Sx and σx?

Sx is sample standard deviation. σx is population standard deviation.

How do I clear a list?

Move to the list name, press CLEAR, then ENTER.

What should I use for more practice?

Use the online calculator, then read the complete guide for statistics and list workflows.