Show that if \(k\) is a positive whole number, then the decimal expansion of \(1/k\) either has a finite number of decimal places or eventually repeats. For example, \[\frac{1}{5} = 0.2 \qquad\text{or}\qquad \frac{1}{17} = 0.\underbrace{0588235294117647}_{} \underbrace{0588235294117647}_{}\ldots\]