Question

a person runs at a speed of 4.5 kilometres per hour. She runs 10 laps on the outside track and 10 laps on the inside track, the inside track has a diameter of 44m. The outside track is 3m thicker than the inside track, how much more minutes did it take her to run the outside lap?

Answer 1

Below

Explanation:

Assuming a circular track

Outside track is 3 m 'thicker ' so the diameter is (44 + 3 + 3) = 50 m

Outside track circumference = pi * d = pi * 50 = 50 pi m

Inside track circumference = 44 pi

Outside 10 laps = .500 pi KM time = .5 pi km / 4.5 km/hr = .3490658 hr

Inside 10 laps = .444 pi KM time = .444 pi km / 4.5 km/hr = .309974

Difference = .039095 hr =2.35 minutes