WEBVTT
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We know that four times five equals 20.
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Pick a true statement. a) Four is a multiple of 20. b) Five is a multiple of 20. c) 20 is a multiple of five. d) 20 is a factor of four.
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And e) 20 is a factor of five.
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It seems like we need to know the definition of the word multiple and of the word factor.
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Factors and multiples are different things.
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They both involve multiplication.
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Factors are what we multiply together to get a number.
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A multiple is the result of multiplying a number by an integer.
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But consider this, four as a multiple of 20.
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If four is a multiple of 20, four has to equal 20 times an integer.
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And an integer is a whole number.
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It’s not a fraction.
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There’s not a whole number we could multiply 20 by to equal four.
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And for that same reason, five can’t be a multiple of 20.
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There’s no integer.
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There’s no whole number that you multiply 20 by that would equal five.
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The next statement says 20 is a multiple of five.
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20 is five times some integer.
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Is there a whole number that we multiply five by that will equal 20?
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Yes, five times four equals 20.
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Four is an integer.
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And that makes 20 a multiple of five. c works.
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Let’s go ahead and consider our last two options. d says 20 is a factor of four.
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Again, if 20 is a factor of four, then you can multiply 20 by some integer and get four.
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Saying 20 is a factor of four is the same thing as saying four is a multiple of 20.
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And it’s not true.
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Saying 20 is a factor of five is the same thing as saying five is a multiple of 20.
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And it’s false.
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The only true statement here is that 20 is a multiple of five.