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we used to put on probability distribution when we're trying to determine the number of
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successes across a space or time.
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in this example we worked at a dealership.
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This house,
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on average,
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four cars a day.
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What is the probability that the dealership will sell exactly five cars in a day
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now to determine that we need to use our puts on probability distribution
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formula P
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X equals X
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equals users number the mean
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want to buy it by,
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I mean x
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X divided by expect x factorial.
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So in this case,
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he or you lose number is always 2.718 Now,
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this is the base of the natural logarithms.
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You should find an E on your calculator
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you don't want to use your calculator here
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because there are 900,000 numbers after this.
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The
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that's what we can determine is the average,
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and that here is four
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and X is the number of successes
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the number of successes were looking for and we're looking for five.
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if we enter that in E,
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I'm not gonna write in 2.718 because I would like you to use your calculator,
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But it is 2.718 to the power
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of negative for multiplied
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by four to power five.
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By five factorial
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looking at
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calculator,
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we can use waken enter in four negative
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four and hit R E squared That gets us
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0.018315 Now I'm leaving the numbers in my calculator
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here Now forward to the power five
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and so four para five
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because 1024
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and that would be divided by five times four
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times 3 times 2 times one.
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now I have left my numbers in the calculator so you may find a rounding air.
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1024 want to abide by
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0.18315 and a few more.
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Quite a few more numbers equals
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18.75 five
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21 Now again,
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I've left the numbers on my calculator,
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but we should get pretty close either way.
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five times four times three times two
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times one is 120
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18.755 to 1.
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Divided by 120
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0.1565
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15.65 present
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using our puts on probability distribution form the
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way determine that if we had on average
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software cars a day,
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there's a 15.65% chance that we would sell five cars in a day.