Final answer:
The student correctly calculated the jogger's speed as 8 miles per hour by dividing 4 miles by 0.5 hours and ensured the speed was reasonable by considering typical running speeds.
Step-by-step explanation:
The student is asking for help with determining the speed of a jogger who ran 4 miles in half an hour. To find the speed in miles per hour (mph), one needs to divide the total distance by the time in hours. Given that the jogger ran 4 miles in half an hour (0.5 hours), the correct calculation for speed would be 4 miles divided by 0.5 hours, which equals 8 miles per hour. This is the jogger's speed.
It is important to check if the answer is reasonable. For example, if the calculated speed was greater than the typical running speed, such as 89 mph, it would be too large and therefore incorrect. Similarly, the speed should have reasonable units, like miles per hour, and be based on the proper time increment—in this case, hours, not minutes or seconds. Also, the significant figures should match the precision of the given data to ensure accuracy.
The information about 40 percent of runners running at speeds of 7.5 mph or slower, and 60 percent running at speeds of 7.5 mph or faster is not directly relevant to calculating the jogger's speed, but it provides context for what is considered a reasonable speed for a jogger.