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We will in this video look at and practice how to
use a number line.
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We will look at what a number line is, and see different examples
on how numbers can be positioned on the number line.
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A number line is a way to represent or visualize
all real numbers.
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Usually you position a few numbers on the number line to show how the line is scaled.
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On this number line in front of you, the number 0 is postioned.
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This indicates that all numbers on the right hand side of the positioned zero are the positive numbers,
and the numbers on the left hand side are the negative numbers.
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If we position the number "a" and the number "b" on this number line, we see that
number "a" > "b", since "a" is on the right hand side of "b".
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We will look at some examples where we position numbers on a number line.
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In the first example, we will position the number 100 on this
number line here.
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Since the number 200 is positioned four steps on the right hand side of zero,
we can conclude that each step corresponds to 50
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We then find the number 100 here.
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In this next example we position the number 3.5 on the number line.
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Here, the numbers 0 and 1 are positioned and there is a vertical line between 0 and 1
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Thus every step on the number line represents 0.5
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If we position number 2 and 3, we can see that number 3.5 should be positioned here.
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Let's look at a similar example.
Here we want to position the number -1.2 on the number line.
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The numbers 0 and -0.3 have already been positioned out.
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We can then conclude that every step on the number line corresponds to
0.3
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If we position the number 0.6 and -0.9 on the number line, then the number on the left hand side should be -1.2