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Identify which of the following arrows represents the position of the square root of 30.
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To estimate the square root of 30, I’m going to think of squares that I already know.
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I know that three squared equals nine.
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I know that five squared equals 25.
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And I know that seven squared equals 49.
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And I know the square roots that correspond to these.
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The square root of nine is three, the square root of 25 is five, the square root of 49 is seven.
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The square root of 25 is five, and the square root of 49 is seven.
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The square root of 30 must fall somewhere between the square root of 25 and the square root of 49.
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And we only have one arrow that falls between five and seven on this line; it’s b.
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The b arrow on the graph is a good representation for the square root of 30.