WEBVTT
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all right, So we are going to do this
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problem without having to use based theorem or even using
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a tree diagram. We just use a visual and
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then you have all the information. We put it
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together and get out. And so the visuals are
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very important in mathematics. So let's begin in the
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table off seasons text. Okay, then you're told
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in the four they used means professor of man's textbook
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. In the winter, they used millions textbook,
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and in the spring in the spring they used Professor
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Moz textbook. Okay. And then we also told
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about satisfaction. We're told that out of the 500
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students who used means textbook, only 200 was satisfied
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, meaning that 300 watt and satisfied. And then
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out of the 300 who used Professor Medians book handed
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on 50 was satisfied, meaning that 150 we're not
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satisfied and 200 used. Professor Moore's book 160 was
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satisfied, meaning that the remaining 40 were not satisfied
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. Now these numbers are very important. So 200
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simply tells you that these other students who used profits
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on Maine's book and they want satisfied and this number
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here tells you that 100 and 50 students used Medians
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book and they were satisfied. And finally, these
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number tells you that these are the students who used
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Professor Moore's book and they were satisfied. Okay,
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he wants that this food. So then the question
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is, even student, uh, during one of
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the semester, the selected at random and admits having
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been satisfied with the textbook is the student most likely
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to have used book by men median On what case
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? Or to figure out that we're going to investigate
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one at a time. So what is the probability
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or the chance? Ah, that the student had
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used means book her means they're using means book.
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Okay, given that they are satisfied with it.
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And this will be total number of strands who used
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to Maine's book and was satisfied, which is 200
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divided by. We need to find the total number
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of students who are satisfied, which was 500 and
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491 of satisfied. Okay, so we're going to
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divide this by 510. This gives use every kind
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three and nine, and then we go to the
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next one probability, But this Didn't he used,
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uh, made Ian's book? Okay, Probability used
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a made Ian's book. Okay. Okay. Having
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been satisfied, given that they will satisfy, this
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will be 100 on 50 divided by 510 which is
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a little behind three. So zero point took not
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three little point 2919494 Then finally, what is a
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chance that the student are the years to mourns?
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Textbook having being satisfied it And these will be 160
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divided by 510 which is zero point 313 So if
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you look at these results, you realize that,
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um, it is more likely that the student had
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to use what he's more likely. No. The
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student used, uh, professor means textbook. Okay
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, Because, as you can see, the chance
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is three continental and the over who is least likely
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the least likely author is, as you can see
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, he's professor media least likely. All the is
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professor movie because you can see the probability of using
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his book. Having been satisfied with it. He's
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on the 0.29 for and that's the end of it
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. Okay. Thank you. Watching