To find a rational number with one decimal place that is between \(\sqrt{17}\) and \(\sqrt{18}\), we first need to determine the approximate values of these square roots.
Calculating the square roots:
- \(\sqrt{17} \approx 4.123\)
- \(\sqrt{18} \approx 4.243\)
Now we can find a rational number with one decimal place that lies in the interval \((4.123, 4.243)\). The numbers we can consider are \(4.1\), \(4.2\), and \(4.3\) (and possibly others).
Among these, \(4.2\) is clearly between \(4.123\) and \(4.243\).
Therefore, a rational number with one decimal place that falls between \(\sqrt{17}\) and \(\sqrt{18}\) is \(4.2\).