Final answer:
To calculate how long it takes for a marathon runner to complete a marathon, divide the total distance by the average speed. For summing distances, add each segment together and report the sum to the correct number of significant figures. Comparing distances in different units requires converting the units to make an accurate comparison.
Step-by-step explanation:
Understanding Marathon Times and Distances
To answer the questions provided, we need to apply mathematical concepts to calculate time and distance in the context of marathon running. In the first scenario, a marathon runner averaging 9.5 miles per hour (mi/h) would take approximately 2.76 hours (or 2 hours and 45 minutes) to complete a 26.22-mile marathon. This is found by dividing the total distance (26.22 mi) by the average speed (9.5 mi/h).
For the second scenario, to find the total distance a marathon runner covers when running in different directions, we simply add the distances together: 9.5 miles + 8.89 miles + 2.333 miles. Using the correct number of significant figures, the total distance is 20.7 miles.
Comparing distances in different units of measure, such as in the case of Sarah and Laura's track events, entails converting units. The 10K distance that Laura will run is 10,000 meters (10 km), which is longer than the 5000 meters (5 km) that Sarah will run in her event.