WEBVTT
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Without using a calculator, order the numbers four, five, and root 19 from smallest to largest.
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Okay so to solve this problem, we’ve got three numbers: four, five, and root 19.
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The number we need to look at is root 19 cause we need to work out the value of this number.
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So in order to help us solve this problem, what I’ve done is I’ve listed the first few square numbers.
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So we’ve got one, four, nine, 16, 25, and 36.
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And we get these square numbers by multiplying a number by itself.
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So one multiplied by one is one.
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Two multiplied by two is four.
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Three multiplied by three is nine, etc.
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So if we look at number 19, we see that the number 19 actually fits between 16 and 25.
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So therefore we can say that root 19 is going to be greater than root 16 but less than root 25.
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Well root 16 is equal to four because four multiplied by four gives us 16.
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And root 25 is equal to five because five multiplied by five gives us 25.
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So therefore, we can say that root 19 is greater than four but less than five.
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So now we can order our numbers, remembering that the question asks us to do it from smallest to largest.
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And we’re going to get four, root 19, and five.
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And we get that and know that because we found that root 19 was between four and five.