Let's evaluate each question one by one:
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Using a number line, what is the approximate value of \(\sqrt{19}\)?
The square root of 19 is between the square roots of 16 and 25, which are 4 and 5.
- \(4.5^2 = 20.25\) (too high)
- \(4.4^2 = 19.36\) (too high)
- \(4.3^2 = 18.49\) (too low)
So \(\sqrt{19} \approx 4.36\).
The answer is: 4.38 (closest option).
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What whole number and rational number to the nearest half is \(\sqrt{105}\) between?
The square root of 105 is between the square roots of 100 and 121, which are 10 and 11.
- \(10.5^2 = 110.25\) (too high)
- \(10.4^2 = 108.16\) (too high)
- \(10.3^2 = 106.09\) (too high)
- \(10.2^2 = 104.04\) (too low)
So \(\sqrt{105}\) is between 10.2 and 10.3, and therefore is also between 10.5 and 11.
The answer is: between 10.5 and 11.
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Using rational approximations, what statement is true?
- \(\sqrt{49} = 7\)
- Therefore, the statement \(\sqrt{49} > 7\) is false.
The correct statement is: \(\sqrt{49} < 7\) is also false. However, \(\sqrt{48} < \sqrt{36}\) cannot be true since \(48\) is greater than \(36\). So only \(\sqrt{48} < \sqrt{36}\) is true.
Therefore, no options exactly match the conclusion.
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Using rational approximations, what statement is true?
- \(\sqrt{81} = 9\)
Therefore, the statement \(\sqrt{81} < 9\) is false.
The correct option is: \(\sqrt{71} < \sqrt{61}\) cannot be true since \(71\) is greater than \(61\). So only \(\sqrt{81} > 9\) is true.
Therefore, the answer is: \(81 −−−√>9\).
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Using rational approximations, what statement is true?
- \(\sqrt{12} \approx 3.46\)
- \(\pi \approx 3.14\)
Here, \(\sqrt{12} > \pi\) is true.
- \(\sqrt{16} = 4\)
Thus, \(\sqrt{16} > 4\) is also true.
The answer is: \(16−−√>4\).
So the answers summary would be:
- 4.38
- between 10.5 and 11
- None of the options exactly match but \(\sqrt{48} < \sqrt{36}\) could be understood.
- \(81−−−√>9\)
- \(16−−√>4\)