WEBVTT

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A statistician for
a basketball team

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tracked the number
of points that each

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of the 12 players on the
team had in one game.

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And then made a stem-and-leaf
plot to show the data.

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And sometimes it's
called a stem-plot.

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How many points
did the team score?

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And when you first look at
this plot right over here,

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it seems a little
hard to understand.

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Understand we have
0, 1, 2 under leaf

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you have all of
these digits here.

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How does this relate
to the number of points

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each student, or each
player, actually scored?

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And the way to interpret
a stem-and-leaf plot

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is the leafs contain--
at least the way

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that this statistician used it--
the leaf contains the smallest

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digit, or the ones digit,
in the number of points

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that each player scored.

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And the stem contains
the tens digits.

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And usually the leaf will
contain the rightmost digit,

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or the ones digit,
and then the stem

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will contain all of
the other digits.

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And what's useful
about this is it

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gives kind of a distribution
of where the players were.

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You see that most of
the players scored

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points that started with a 0.

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Then a few more scored
points that started with a 1.

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And then only one score scored
points to started with a 2,

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and it was actually 20 points.

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So I'm going to actually
write down all of this data

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in a way that maybe
you're a little bit more

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used to understanding it.

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So I'm going to write
the 0's in purple.

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So there's, let's see, 1,
2, 3, 4, 5, 6, 7 players

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had 0 as the first digit.

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So 1, 2, 3, 4, 5, 6, 7.

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I wrote seven 0's.

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And then this player also
had a 0 in his ones digit.

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This player, I'm going to
try to do all the colors,

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this player also had
a 0 in his ones digit.

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This player right here
had a 2 in his ones digit,

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so he scored a
total of 2 points.

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This player, let me
do orange, this player

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had 4 for his ones digit.

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This player had 7
for his ones digit.

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Then this player had
7 for his ones digit.

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And then, let me see, I'm
almost using all the colors,

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this player had 9
for his ones digit.

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So the way to read this is, you
had one player with 0 points.

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0, 2, 4, 7, 9 and 9.

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But you can see, and
it's kind of silly

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saying the zero
was a tens digit,

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you could have even
put a blank there.

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But the 0 lets us
know that they didn't

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score anything in
the tens place.

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But these are the actual
scores for those seven players.

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Now let's go to the next row
in the stem-and-leaf plot.

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So over here, all of
the digits start with,

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or all of the points start with
1, for each of the players.

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And there's four of them.

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So 1, 1, 1, and 1.

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And then we have this
player over here,

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his ones digit, or her
ones digit, is a 1.

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So this player,
this represents 11.

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1 in the tens place,
1 in the ones place.

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This player over
here also got 11.

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1 in the tens place,
1 in the ones place.

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This player, let me
do orange, this player

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has 3 in the ones place.

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So he or she scored 13 points.

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1 in the tens place,
3 in the ones place.

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13 points.

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And then I will
do this in purple.

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This player has 8
in their ones place.

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So he or she scored 18 points.

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1 in the tens place,
8 in the ones place.

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18 points.

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And then finally,
you have this player

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that has the tens digit is a 2.

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And then the ones digit is a 0.

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I'll circle that in yellow.

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It is a 0.

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So he or she scored 20 points.

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So looking at the
stem-and-leaf plot,

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we were able to extract out
all of the number of points

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that all of the players scored.

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And once again, what
was useful about this,

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is you see how many players
scored between 0 and 9 points,

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including 9 points.

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How many scored between
10 and 19 points,

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and then how many scored
20 points or over.

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And you see the distribution
right over here.

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But let's actually
answer the question

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that they're asking
us to answer.

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How many points
did the team score?

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So here we just
have to add up all

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of these numbers
right over here.

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So we're going to add up, I'll
start with the largest, so 20

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plus 18 plus 13 plus 11 plus
11-- 13, 11, 11-- plus 9 plus 7

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plus 7 again plus 4 plus 2.

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Did I do that right?

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We have two 11's, then a 9,
then two 7's, then a 4 then a 2,

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and then these two characters
didn't score anything.

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So let's add up all
of these together.

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So 0 plus 8 is 8, plus 3 is
11, plus 1 is 12, plus 1 is 13,

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plus 9 is 22, plus
7 is 27, 34, 38, 40.

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So that gets us to 40.

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Let me do that one more time.

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8, 11, 11, 12, 13, 22, 29, 29,
and then 29, 36, 40, and 42.

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Looks like I actually
might have messed--

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let me do that one more time.

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This is the hardest
part, adding these up.

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So let me try that
one last time.

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I'm just going to
state where my sum is.

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So 0, 8, add 3, 11, 12,
13, 22, 29, 36, 40, 42.

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So it's a good thing that
I double checked that.

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I made a mistake the first time.

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4 plus 2 is 6, 7, 8, 9, 10.

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So we get to 102 points.

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The team, in total,
scored 102 points.