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Standard Deviation Binomial Distribution in Easy Steps

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Standard Deviation Binomial Distribution: Overview

standard deviation binomial distribution

A coin toss can be a binomial experiment.


A binomial distribution is one of the simplest types of distributions in statistics. It’s a type of distribution where there is either success, or failure. For example, winning the lottery: or not winning the lottery. Most elementary statistics classes require you to find the standard deviation of the binomial distribution. This can be a challenge, because the variance and standard deviation formulas are daunting when you first look at them. However, if you break the formulas down into steps, they don’t look as scary. This how to will tell you how to find a standard deviation binomial distribution in just a few steps.

Standard Deviation Binomial Distribution: Steps

Step 3:  Make a probability distribution chart. If you’re not sure how to make one, see: How to construct a probability distribution.

probability distribution chart

  • Step 4:  Square the top number (X) in each column and multiply it by the bottom number in the column (P(X)). For example 0²*0.09 from the first column, 1²*0.07. Repeat for all columns.
  • Step 5: Add all of the numbers in step 4 together.
  • Step 6: Subtract the number you found in step 2 from the number you found in step 5.
    Step 5-Step 2=?.
  • Step 6: Take the square root of the number you found in step 6.
    √Step 6=?

That’s how to find a standard deviation binomial distribution!

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11 thoughts on “Standard Deviation Binomial Distribution in Easy Steps

  1. Lisa Barcomb

    With this section its okay until you get down to the 4th step and then I am lost although this article did help me figure out how to finish the problem. So I am glad that they do have this information in here for us to look at so we have something to fall back on.

  2. Rebecca Gamble

    I wish I would have read this information before I did the long walk to ace for help! I chart is a lot of help but I agree the steps are a little confusing, just read over them two times and it will make sense.

  3. Donna Allen

    Your explanation here is much simpler and easier to follow than the one given in the book. I agree, it’s great to have this blog to fall back on.

  4. Catherine Flanagan

    This blog did help me to understand standard deviation better, but it would be better if the problem was written out with each step. I think this would help all us visual learners!

  5. Lisa Barcomb

    This blog really helped me with the probability chart because I was really confused for the longest time as I am sure you are well aware of. I really like looking on this because I feel like I get a better understanding.

  6. angie widdows

    This example is very helpful because it has the links to other problems that we have already covered. We learn things in previous sections but it is always nice to be able to go back for a refresher.