To find Jess's average speed in miles per hour, we can use the formula:
\[ \text{Speed} = \frac{\text{Distance}}{\text{Time}} \]
- Distance: Jess rides \( \frac{3}{4} \) miles.
- Time: Jess rides for 4 minutes. To convert this to hours, we can divide by 60:
\[ \text{Time in hours} = \frac{4 \text{ minutes}}{60} = \frac{1}{15} \text{ hours} \]
Now we can calculate her average speed:
\[ \text{Speed} = \frac{\frac{3}{4} \text{ miles}}{\frac{1}{15} \text{ hours}} = \frac{3}{4} \times \frac{15}{1} = \frac{3 \times 15}{4 \times 1} = \frac{45}{4} \text{ miles per hour} \]
\[ \frac{45}{4} = 11.25 \text{ miles per hour} \]
Thus, Jess's average speed is 11.25 miles per hour.