An amateur race car driver competed in two heats yesterday that were both 26 kilometers long. During the first heat, his time was 6 minutes. For the second one, he clocked in at 7 minutes. What was his average speed?

Write your answer as a whole number or as a decimal rounded to the nearest tenth.
kilometers per hour

1 answer

To calculate the average speed of the amateur race car driver over the two heats, we need to first determine the total distance covered and the total time taken.

  1. Total Distance: The driver competed in two heats, both 26 kilometers long. Therefore, the total distance is: \[ \text{Total Distance} = 26 \text{ km} + 26 \text{ km} = 52 \text{ km} \]

  2. Total Time: The time for the first heat was 6 minutes, and the time for the second heat was 7 minutes. Converting these times into hours (since we want the average speed in kilometers per hour): \[ 6 \text{ minutes} = \frac{6}{60} \text{ hours} = 0.1 \text{ hours} \] \[ 7 \text{ minutes} = \frac{7}{60} \text{ hours} \approx 0.1167 \text{ hours} \] Now, we can calculate the total time: \[ \text{Total Time} = 0.1 \text{ hours} + 0.1167 \text{ hours} \approx 0.2167 \text{ hours} \]

  3. Average Speed: The average speed is calculated by dividing the total distance by the total time: \[ \text{Average Speed} = \frac{\text{Total Distance}}{\text{Total Time}} = \frac{52 \text{ km}}{0.2167 \text{ hours}} \approx 239.0 \text{ km/h} \]

Thus, the average speed of the race car driver is approximately 239.0 kilometers per hour when rounded to the nearest tenth.