Let's tackle each question one by one.
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Example of a rational number between \( \sqrt{10} \) and \( \sqrt{11} \):
- We know \( \sqrt{10} \approx 3.16 \) and \( \sqrt{11} \approx 3.32 \).
- A rational number in this range could be \( \frac{16}{5} = 3.2 \), which is between \( \sqrt{10} \) and \( \sqrt{11} \).
- Thus, one example is \( \frac{16}{5} \).
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Irrational number between \( \sqrt{14} \) and \( \sqrt{18} \):
- We approximate \( \sqrt{14} \approx 3.74 \) and \( \sqrt{18} \approx 4.24 \).
- Among the options:
- \( \sqrt{15} \approx 3.87 \) is between those two values.
- Therefore, the irrational number between \( \sqrt{14} \) and \( \sqrt{18} \) is \( \sqrt{15} \).
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How many irrational numbers are there between \( \sqrt{11} \) and \( \sqrt{17} \):
- We calculate \( \sqrt{11} \approx 3.32 \) and \( \sqrt{17} \approx 4.12 \).
- There are an infinite number of irrational numbers between any two distinct real numbers.
- Thus, the answer is an infinite number.
In summary:
- \( \frac{16}{5} \) is a rational number between \( \sqrt{10} \) and \( \sqrt{11} \).
- \( \sqrt{15} \) is an irrational number between \( \sqrt{14} \) and \( \sqrt{18} \).
- There are an infinite number of irrational numbers between \( \sqrt{11} \) and \( \sqrt{17} \).