WEBVTT
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Hi. We're looking at question 112 where they've identified
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a group of Children with hair color and type of
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hair and part A wants us to fill in the
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table. So we're gonna start with the easier ones
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and we can fill in the total for the brown
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by taking 20. 20 plus 80 equals 100.
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So 100 will go in that row and then,
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um, for the blonde, because we know our
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total is 20 and we know 15 of them have
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straight hair. What's leftover? Must be our wavy
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hair. So five would be a result there.
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Um, we can't fill in too much with the
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black hair from the column because we only have one
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number, but from the red hair weaken, do
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three plus 12 is 15. So now we have
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some options to fill in what's left. Um,
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the easiest thing it looks like to me to fill
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in the total for the black hair would be to
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take the total for the row, which is the
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215. And we'll subtract the 15 from the red
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, the 20 from the blonde and the 100 from
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the brown which will give us a tea. So
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80 is what goes in the column for the black
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. So then, to calculate the value for the
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straight black, we'll do a T minus 15 which
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is 65. So 65 will go right there and
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then we're only missing one thing. Now that's the
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total for the, um, straight hair. So
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we'll take 80 plus 15 close 65 plus 12 and
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and those up. Then we end up with 172
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. So 172 goes there. So that fills in
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our table, which is part a. And then
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we're going to be using those values to answer the
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remaining questions. And for this particular question, they
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just have the answers infraction for math. So I
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have to find the probability of wavy hair. We're
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just going to find the total number of students with
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wavy hair, which they actually gave us in the
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original part of the question. Just 43 out of
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the total number of students, which is 215 and
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in this case, the answer's air infraction form.
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So we don't need to divide it for brown or
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blond hair. We have to look at the totals
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in those two columns, so the total in the
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brown hair column is 100 and the total in the
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blood hair column is 20 that was given to us
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out of our 215 students. So that's 120 over
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to 15 and then wavy brown hair. So this
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one, we actually need to find the wavy row
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brown her column and where they need, which is
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it 20. And that's out of the 215 um
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, total students. So that's those three sections.
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Now we'll continue on and have red hair given straight
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hair. So this is one of those given questions
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where we need to consider what, um, what
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we're working out of. So we're looking on Lee
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in the straight hair row for any of our information
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because it's given that it's straight hair. We want
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the red hair in the straight hair rope, which
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is 12. And then again, we are only
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considering straight haired students, so that's gonna be 12
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out of 1 72 So there's 12 students out of
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172 students with straight hair, 12 of them have
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red hair, so that's our probability There for a
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part. F. They tell us that B is
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the event of a child having brown hair, and
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they want us to find the probability of that complement
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of Brown Will Complement is meeting. It's not brown
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, so it's a probably of not brown hair or
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probably, if not to be so for not brown
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hair that would include the red hair, the blonde
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hair and the black haired students. Or we can
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just say that, not brown hair students. So
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we could just take the total of 2 15 and
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subtract the 100 students with brown hair out of one's
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out of the 215 students that we have, So
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that would be 1 15 over to 15. Another
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way of doing that would be also to get the
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1 15 would be to take the, um,
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20 blonde haired students, plus the 80 black haired
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students, plus the 15 red haired students that would
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get us sustain number with the same answer. And
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then finally, it asks us to, um,
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find or two right, explain in words. It
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says, What does the compliment terms of b represent
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. So the V compliment will include anyone who doesn't
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have brown hair. So it will include Children with
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, um, long hair, red hair and black
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hair. And that's all there is to it.
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Thank you.