WEBVTT
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Hi. So we're answering the question that I asked
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about the randomly selected senator. We know that's a
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randomly selected senator. We want the probability that,
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um, it's a Democrat, given that we know
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it's a randomly selected senator from the November 2016 re
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election, which is what I have written here on
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the screen. So if you remember to calculate a
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given kind of probability, for example, if we
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have the probability of a given B, that's equal
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to the probability of A and B together over the
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probability of B. So we're gonna do the same
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kind of thing here to answer this question and put
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it in terms of the question itself. So the
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probability that it's a Democrat, given that they're re
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electing in November 2016. So that would be equal
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to the probability that it's a Democrat and the November
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2016 election over the probability of all the senators in
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the November 2016 election. So we're gonna look at
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our table and the 1st 1 the numbers given to
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us. We just need to look in the Democrat
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column and go down to the road. This is
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re elect November 2016 and you'll see that there's 10
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senators in that column, and then we're gonna use
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the road that says November 2016 reelection. We would
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need to add those up if you haven't already done
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that. So 10 plus 24 which is 34 and
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then we use our calculator to divide that and we
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end up with zero point 29 for one, and
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that's all there is having a.