1. The problem asks: What fraction of an hour is 24 minutes?\n\n2. We know that 1 hour = 60 minutes.\n\n3. To find the fraction of an hour that 24 minutes represents, we use the formula:\n$$\text{Fraction} = \frac{\text{minutes}}{\text{total minutes in an hour}} = \frac{24}{60}$$\n\n4. Simplify the fraction by dividing numerator and denominator by their greatest common divisor, which is 12:\n$$\frac{\cancel{24}^{2}}{\cancel{60}^{5}} = \frac{2}{5}$$\n\n5. So, 24 minutes is $\frac{2}{5}$ of an hour.\n\nFinal answer: $\boxed{\frac{2}{5}}$