Final answer:
To find the bike's speed in mi/hr after riding for 80 minutes and going 45 miles, we convert the time to hours (1.333 hours) and then divide the distance by the time, resulting in a speed of 33.75 mi/hr.
Step-by-step explanation:
To find the bike's speed in miles per hour (mi/hr), we need to calculate the average speed using the formula:
Speed = Distance ÷ Time
First, we need to convert the time from minutes to hours since the speed needs to be in mi/hr:
80 minutes = 80 ÷ (1/60) hours = 4/3 hours (or 1.333 hours).
Now, we use the formula:
Speed = 45 miles ÷ 1.333 hours = 33.75 mi/hr
Therefore, the correct answer is A. 33.75 mi/hr.