Marco's bicycle speed rate: 20 miles in 2 1/2 hour
To get the average speed or rate, we use the following formula:
[tex]\text{Speed = }\frac{total\text{ distance}}{\text{total time }}[/tex]Using the formula, we get:
[tex]\text{speed = }\frac{total\text{ distance}}{\text{total time}}=\frac{20\text{ miles}}{2.5\text{ hr}}=\frac{8\text{ miles}}{1hr}=8mi.\text{ per hour}[/tex]Therefore, the average rate of Marco when doing bicycle is 8 miles per hour.