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Hello, my name is david.
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In this video, we'll cover the distribution binomial.
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We'll suppose in this problem that we'll buy 20 plants and that the probability of that the plantes survive is of 95 % or 0 .95.
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Now, for the part a, we'd want to find the probability of that 20 plants overvivian.
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So, for that we'll use the next function binomial p -d -f where we're to put n p -i -x respectively and this function is represented by the formula n is coge x multiplied by the probability to the power of x multiplied by 1 minus the probability to the power of n minus x.
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Now, for this we can use the function in your calculator we'll use the formula.
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So we'll use the formula for now.
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So the probability of that 20 survive is equal to the function binomial or binom pdf, where we'll put 20 .95 .20.
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And if we put in the formula, we'll 20, it's to goge 20 multiplied for 0 .95 to the power of 20 that i did the power of 20 multiplied by 1 minus 0 .95 to the power of 20 minus 20.
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Now 20 minus 20 is 0 and any number at power of 0 is 1 so this term will be 1 now 20 then to do 20, then to then our result for the probability of 20, it will be 0 .95 to the power of 20, that we do 0 .35 85.
02:30
Now, in best to use the formula, also we use the function of the calculator, that would be the same result, and we would not be to put all those numbers in the formula.
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Now, for the part b, we want to find the probability that to do do do minus or equal to 16.
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But for this, we have to find the probability of that one survive, more the probability of that two survive, plus the probability that three survive, until that we get to sum up the probability that 16 survive.
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Now, in best to repeat the formula anterior, 16 times, we can use other different function, that's called binom binom cd -d -f, which means the probability cumulative to a certain point.
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And this function is we will to find this sum of all these probabilities...