1. **State the problem:** Sam usually runs for 48 minutes each day. On Monday, he completed only $\frac{1}{4}$ of his usual workout. We need to find the time Sam spent running on Monday in minutes. 2. **Formula and explanation:** To find the time spent running, multiply the usual time by the fraction completed. $$\text{Time on Monday} = \text{Usual time} \times \text{Fraction completed}$$ 3. **Substitute the values:** $$\text{Time on Monday} = 48 \times \frac{1}{4}$$ 4. **Calculate:** $$48 \times \frac{1}{4} = \frac{48}{4} = 12$$ 5. **Answer:** Sam spent 12 minutes running on Monday.