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Construct a probability distribution in Easy Steps

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Construct a probability distribution: Overview

construct a probability distribution

A normal distribution curve is one kind of probability distribution.


A probability distribution is basically a chart of what the probability of an event happening is. It’s a way of quickly viewing the event, and the probability of that event. Probability distribution charts can get quite complex in statistics. For example, a normal distribution or t-distribution chart usually requires some form of technology (like Microsoft Excel or the TI-83 calculator) to create. However, you can construct a basic probability distribution showing events and probabilities in a few easy steps.

Construct a probability distribution: Steps

Sample question: Construct a probability distribution for the following scenario: the probability of a sausage making machine producing 0, 1, 2, 3, 4, or 5 misshapen sausages per day are 0.09, 0.07, 0.1, 0.04,0.12, and 0.02.

  • Step 1: Write down the number of widgets (things, items, products or other named thing) given on one horizontal line. In this case, the widgets in this question are the “misshapen sausages”.
  • Making the first line of the probability distribution chart.

    Making the first line of the probability distribution chart.

  • Step 2: Directly underneath the first line, write the probability of the event happening.
    • The probability of the sausage machine producing 0 misshapen sausages a day is 0.09, so write “0.09” directly under “0”.
    • The probability of the sausage machine producing 1 misshapen sausages a day is 0.07, so write “0.07” directly under “1”.
    • The probability of the sausage machine producing 2 misshapen sausages a day is 0.1, so write “0.1” directly under “2”.
    • The probability of the sausage machine producing 3 misshapen sausages a day is 0.04, so write “0.04” directly under “3”.
    • The probability of the sausage machine producing 4 misshapen sausages a day is 0.12, so write “0.12” directly under “4”.
    • The probability of the sausage machine producing 5 misshapen sausages a day is 0.02, so write “0.02” directly under “5”.

Probability Distribution
That’s how to Construct a probability distribution!

11 thoughts on “Construct a probability distribution in Easy Steps

  1. Lisa Barcomb

    This blog is alittle complicated I had problems with this on the homework. For some reason I did not get the jest of the table until I did it several times. I wish it could be alittle more understanding then what it is. I felt like I need more examples.

  2. Brian Hicks

    I agree. The practice problems in the book asked us to construct probability distribution tables without giving the individual probabilities. It was very vague and the examples (p. 40-41 examples 4 & 5) did not correlate to the practice problems (p.42 #2 & 3).

  3. Christine Woll

    I understand how to make a probability distribution when the numbers are given, what I’m not understanding is how to create a probability distribution when p(x) is not given. Like in the book Example 3a asks us to construct a probability distribution for the number of boys in a family with 4 children. When I try the equation p(x)=(1/2)^x it doesnt seem to work out to equal 1. I’m still confused :(

  4. Christine Woll

    Scratch that, I went on to do the homework and everything was gravy. This stuff isn’t too bad! I like the blog, it tends to explain things a lot better than the book does.

  5. Lisa Barcomb

    The probability questions to me are alittle hard to understand. I think maybe I am reading more into them then need to be. But they are not my favorite questions by no means. Everyone has something they are better in doing then others and this is not mine. I wish it was.

  6. yvonne walton

    I purchased your book on-line and ran the program but cannot find it anymore it did not create a decktop icon. can you tell me how to do this or when the book will arive. this is strange because i was using it to see how many articles would be possible to find solutions to my statistics problems.

  7. Stephanie

    Yvonne, the original email with the link was good for 3 downloads…try finding the original email and downloading again. If that doesn’t work, the file should be in your downloads folder. If you have Windows, go to My Documents->Downloads. You can also try a Windows search (search for “Practically”).

  8. Sayaka

    Make a table and a histogram showing the probability distribusion for the random variable.

    W=1 if a randomly chosen letter is A, E, I, O, or U and 2 otherwise.

    I have problems with understanding English,
    And I don’t know what the problem means.
    Could anyone please help me?