Standard Deviation How to Calculate by Hand (Formula)

Learn how to calculate standard deviation by hand in this free math video tutorial by Mario's Math Tutoring. We discuss what Standard Deviation is and a formula for how to find it.

0:25 What is Standard Deviation
0:43 Formula for Calculating Standard Deviation
1:22 Example 1 Find the Standard Deviation of the Quiz Scores 5, 8, 8, 9, 10
1:47 Make a Table to Help Compute the Standard Deviation
2:30 Step 1 Calculate the Mean (Average)
2:49 Step 2 Take the Difference of Each Data Point and the Mean
3:02 Step 3 Square the Deviations
3:10 Step 4 Sum the Squares of the Deviations
3:14 Step 5 Divide by How Many Data Points
3:20 Step 6 Take the Square Root

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[jackhorowitz]

Mario, I should mention that you showed the standard deviation calculation for a population. Standard deviations are more commonly calculated for samples. The calculation, as I'm sure you're aware changes so that the denominator is n-1 instead of n. I think you should mention that in your video. Just my opinion

[valeriaprado]

Thank you so much! I had a quiz and didnt know anything about standard deviation. Im glad I clicked on your video!😊👏🏻

[williammiller]

I was curious about deviation cuz I watched a video called ''The missile knows where it is..''. Anyways, 2 minutes in and every variable and description on how the formula basically works is easily described and understandable with practical math knowledge! thumbs up to this math teacher!

[mathhelpmadeeasy]

Great explanation of Finding Standard Deviation! Thanks

[learning_at_home.]

Very nice
I love to your lectures so much!

[MotM]

That was perfect thank you for the help

[kaylateplica]

Thank you so much this was very helpful!!!

[Bizourelicious]

Shouldn’t that be the sum of the deviation square divided by (n-1)?

[twiedenfeld]

I'm curious about the notation you're using. Isn't mu generally used for mean in populations and x bar used for samples?

[helloitisme]

Wait, isn't it n-1 instead of n?

[Shonade_Malik]

I hope my grade 8 mind can understand this...

[amaniaman]

I was with you until the end. Take the square root part. I got 2.8, then I'm stuck

[dannychenski]

You've never given an explanation im confused by