In a 5.00km race, one runner runs at a steady 11.6km/h and another runs at 15.0km/h. How long does the faster runner have to wait at the finish line to see the slower runner cross?

Question

In a 5.00km race, one runner runs at a steady 11.6km/h and another runs at 15.0km/h. How long does the faster runner have to wait at the finish line to see the slower runner cross?

Answer 1

15t = 5

t = 0.333h = 20 min.

11.6t = 5
t = 0.431h = 26 min.

T = 26 - 20 = 6 min. waiting time.

Answer 2

To find out how long the faster runner has to wait at the finish line to see the slower runner cross, we need to calculate the time it takes for the slower runner to complete the race.

Distance = Speed × Time

For the slower runner:
Distance = 5.00 km
Speed = 11.6 km/h

Time = Distance / Speed
Time = 5.00 km / 11.6 km/h

Calculating the time taken by the slower runner:
Time = 0.431 hours

Now, we need to determine the distance the faster runner covers in that time.

Distance = Speed × Time

For the faster runner:
Speed = 15.0 km/h
Time = 0.431 hours

Calculating the distance covered by the faster runner:
Distance = 15.0 km/h × 0.431 hours

Distance = 6.465 km

Since the race is only 5.00 km long, the faster runner would have to wait 6.465 km - 5.00 km = 1.465 km at the finish line to see the slower runner cross.

Answer 3

To find out how long the faster runner has to wait at the finish line to see the slower runner cross, we need to calculate the time it takes for the slower runner to complete the race.

First, let's determine the time it takes for each runner to complete the race.

For the slower runner:
Distance = 5.00 km
Speed = 11.6 km/h

Using the formula Time = Distance / Speed, we can calculate the time it takes for the slower runner to complete the race:

Time = 5.00 km / 11.6 km/h ≈ 0.431 hours ≈ 25.9 minutes

So, the slower runner takes approximately 0.431 hours (or 25.9 minutes) to complete the race.

Now, let's find out how long the faster runner has to wait at the finish line to see the slower runner cross.

For the faster runner:
Speed = 15.0 km/h

Since both runners start the race at the same time, the faster runner will cross the finish line in less time than the slower runner. Therefore, the faster runner will have to wait for the remaining time that the slower runner takes to complete the race.

Waiting time = Time taken by slower runner - Time taken by faster runner
= 0.431 hours - 0 hours (since the faster runner finishes before the slower runner)

Hence, the faster runner does not have to wait at the finish line to see the slower runner cross because the faster runner finishes first.