WEBVTT

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We're asked to subtract and
simplify the answer, and we

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have 8/18 minus 5/18.

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So subtracting fractions
is very

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similar to adding fractions.

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If we have the same denominator,
the denominator

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in the difference is going
to be the same as the

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denominators in the two
numbers that we're

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subtracting, so it's
going to be 18.

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And our numerator is going to be
the difference between the

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numerators.

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So in this case, it is 8 minus
5, and this will be equal to 3

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over 18, which is the answer,
but it's not completely

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simplified, because both 3 and
18 are divisible by 3.

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So let's divide them
both by 3.

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So you divide 3 by 3, you divide
18 by 3, and you get 3

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divided by 3 is 1.

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18 divided by 3 is 6,
so you get 1/6.

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And just to see this visually,
let me draw 18 parts.

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Let me draw 18 parts here.

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So it might be a little bit
of a messy drawing.

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I'll try the best I can.

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So let me draw six in
this direction.

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So that is three right there.

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We have another three,
so that's six parts.

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And then let me split this
into three columns.

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So there we go.

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We have 18 parts.

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Now 8/18 is equal to one,
two, three, four,

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five, six, seven, eight.

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That's 8/18.

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And now we want to subtract five
of the eighteenths, so we

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subtract one, two, three,
four, five.

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Now, what do we have
left over?

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Well, we have three of the
eighteenths left over, so you

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have that right there.

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You have three of the
eighteenths left over.

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Now, if you turn three of the
eighteenths into one piece,

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how many of those bigger
pieces do you have?

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This is one of those
big pieces.

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Now, where are the other ones?

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Well, this is another big
piece right here.

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This is another big piece
right here, another one,

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another one, and another one.

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If you had 18 pieces and you
merged three of the pieces

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into one, then you actually end
up with only six pieces.

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You end up with six pieces.

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Hopefully, you see that each row
is one of the pieces now,

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and the blue is exactly one
of the six, so 3/18

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is the same as 1/6.

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