Question

select the correct answer.

bartolo is running a race. he determines that if he runs at an average speed of 15 feet/second, he can finish the race in 6 seconds. if he runs at an average speed of 18 feet/second, he can finish the race in 5 seconds.

bartolo thinks that the fastest he can run is 30 feet/second. how long would it take him to finish the race at this speed?

2 seconds
2.5 seconds
3 seconds
3.5 seconds

Explanation:

Calculate the distance of the race

$$ d = 15 \text{ ft/s} \times 6 \text{ s} = 90 \text{ ft} $$

Verify the distance with the second scenario

$$ d = 18 \text{ ft/s} \times 5 \text{ s} = 90 \text{ ft} $$

Calculate the time at the new speed

$$ t = \frac{90 \text{ ft}}{30 \text{ ft/s}} = 3 \text{ seconds} $$

Answer:

• 2 seconds
• 2.5 seconds
• 3 seconds (Correct answer)
• 3.5 seconds