Explain why if a runner completes a 6.2â-mi race in 32 âmin, then he must have been running at exactly 11 âmi/hr at least twice

Response:

As the runner accelerates to peak speed, he then decelerates to reach the finish line.

Step-by-step clarification:

Maintaining a steady pace of 11 mph throughout his 32-minute run, the distance covered would be:

This indicates that to complete the 6.2-mile race, the runner needs to exceed 11 mph. Assuming he starts from a standstill, he accelerates to over 11 mph. Since he comes to a stop at the finish line, the runner must slow down from his higher speed (which is above 11 mph), passing through 11 mph before ultimately halting.