Question

On a particular day, caroline decided to run two laps of a park of which each lap is 1. 2kms. She takes 12 minutes to run her first lap, and she runs her second lap at an average speed of 7 km/h. Determine her average speed over the two laps.

Answer 1

Answer:

6.46 km/h

Explanation:

Total distance d = 2 * 1.2 = 2.4 km

Total time t = 12 min + t' where t' is the time taken for second lap.

t' = 1.2 km/(7 km/h) = 1.2/7 hours

so t = 12/60 hours + 1.2/7 hours = 0.3714 hours

The average speed = d/t - 2.4/0.3714 = 6.46 km/h