WEBVTT
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Yeah, Hi. We're looking at question 109 and
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there are several parts to this question, so we'll
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just work our way through them, starting with part
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A where they want us to fill in the column
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that says, um, workout, getting suicides for
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individuals over 64. So they've gathered information on suicides
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from different ages, races and sexes and compile them
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into a table. But the table is incomplete.
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So since we're filling in a column, we're going
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to use our row information to calculate each of these
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. So starting with the white male row to be
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able to fill in the column over 64 we start
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with the total, which is 22,050 and then we're
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going to subtract. Each of the values that we
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know so well do is attract to 10 for the
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one through 14 age bracket, 3360 for the 15
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through 24 age bracket, and 13,610 for the 25
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3 64 bracket, which leaves 4870 for the over
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64. We're gonna follow a similar pattern for the
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white female, the total for the row is 4930
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and we will subtract 80 for the first column,
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580 for the second and then 3380 for the third
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, leaving us with a total for the over 64
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of 890. Now we'll do the same thing with
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the blackmail. The total is 1670. Then we'll
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subtract the 10 from the first column, the 4
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60 from the second column and that 1060 from the
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third column, which leaves us with 140 for that
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room. And then we'll do the black female rose
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, similarly, 330 and subtract the zero for the
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first column, the 40 for the second column and
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the 2 70 for the third column, leaving us
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with 20 for the over 64 set. And then
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I'm changing to Red because we're going to jump to
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totals because they all others row is empty. We
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can't fill that one in on its own, but
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we can fill in our total and then use all
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of our information to go back and get the aloe
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others spot. So our total we have 29,760 and
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then we can subtract each of the values from that
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row. So that would be 3 10 and subtract
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4650 for the second column in 18,780 for the third
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column, which leaves us with 6020. Now we
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can use that 6020 here and subtract are answers that
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we got right here. So we'll subtract the 4870
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subtracted 8 90 Subtract the 1 40 subtract the 20
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. So you want to be careful that you've done
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your subtractions. They're carefully to make sure that you
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get the right answers so that this one's correct.
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And so we have 100 for the all others.
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So we've now successfully filled in the overt 64 column
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for part A for part B. We're going to
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work similarly through the all others row now. So
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now we're cause we're working the road. We're gonna
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use the columns to do the subtraction. So for
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the one through 14 set, we have a total
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of wow how that happened. Um a total.
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I mean, erase those for you and we'll go
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back and try this again. So we have a
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total of 310 and we're going to subtract the 210
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and subtract the 80. So I'm just going down
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the column in this case and then subtract the 10
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and subtract the zero. So that leaves for the
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all others. I'm 10. Similarly, I'm gonna
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take the total for the column 15 to 24 which
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is 4650. And I'll subtract the white male,
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which is 3360 and subtract the white female, which
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is 5 80 and then subtract the blackmail, which
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is for 60 and then subtract the black female,
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which is 40. And that least may for with
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210 to fill in the all other spot 25 to
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64 will work the same way. I'm gonna start
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with my total of the bottom 2780 and then I'm
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just gonna work my way down the columns. So
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I'm gonna start with the weight males, and you
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could work your way up the column if you prefer
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. It obviously won't change the answer of the end
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on dhe. So I'm just gonna subtract each of
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the values in the column from my total. And
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that leaves me with 460 now again with this one
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because you may not have done part a yet with
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the over 64 um, column. I'm gonna skip
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down to totals so that we can fill these in
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with the information that we have here. So our
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total for the whole table is 2000 or 29,760 and
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then I'm going to be attracting the column, because
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again, if we're working on a row, we're
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gonna go down our columns. So I subtract the
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22,050 from the top and then subtract the 4930 and
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then subtract the 1670 and then subtract the 330 and
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that leaves me with 780. And now I can
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use that value to figure out my over 64 with
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the other information that I have. So I'm gonna
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take the 7 80 then all of this stuff that
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I just calculated. So also tracked the 10 the
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210 and the 4 60 So it's important to make
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sure those values are accurate. Um, And so
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I end up with 100 which is also what I
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got her A If you did that for the over
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64 in all others column So I'm pretty sure that
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I didn't make any subtraction errors. They're So now
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we could move on to part C and calculate the
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probability of, um, it being on the that
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the randomly selected individual was a white male. So
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I'm gonna find the total of the white males which
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it tells me on the table is 22,050. And
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I'm going to divide that by the total in the
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table or the total people surveyed, which was 29,760
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. And when you divide that on your calculator,
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you get 0.74 I can do the same thing with
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the black females. There were 330 of those out
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of our total of 29,760 that were surveyed. So
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that calculates out to 0.11 for my total and then
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the probability that someone is black. Now, in
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this case, I have to take into consideration the
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black females and the black males. So the black
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males are 1670. The black females are 330 over
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the total of seven or 29,760. So when I
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add those together, I get 2000 over 29,760.
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So the probability that a randomly selected individual is black
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would be 0.67 and then we'll finish this question up
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with parts F N G Um, her F is
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a black or white male, so I want to
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find the black males are 1670 and the white males
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are 22,050. They haven't limited. My totals are
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still 29,000 760. So when I add those two
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together I get 23,720 over the 29,760 which gives me
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0.797 for that probability. And finally the last one
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ass s party finds us asked us to find out
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if the individuals of the individuals who are over 64
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find the probability that a randomly selected individual was a
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black or white male. So we're basically on Lee
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looking at that column that we filled in of the
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over 64 set. And so the, um,
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white males in the black males in that section So
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the black males were 140 and the white males were
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4870 and our total this time is only the total
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for the over 64 column. In that total was
139
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6020. So then I'm gonna take the 1 40
140
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plus the 48 70 which is 5010 and divide by
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60 20 which equals 0.83 and we're done with that
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question.