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3 years ago

Swim 2km at 3km/h. Run at 12km/h for 1 ½ hours. Cycling 55km at 30 km/h. What is the mean overall speed.

Physics

1 answer:

exis [7]3 years ago

5 0

Answer:

t1 = S1 / V1 = 2 km / 3 km/hr = 2/3 hr where S1 = 2 km

S2 = 12 km/hr * 3/2 hr = 18 km where t2 = 3/2 hr

t3 = S3 / V3 = 55 km / 30 km/hr = 11/6 hr where S3 = 55 km

T = t1 + t2 + t3 = 4/6 + 9/6 + 11 / 6 = 24/6 = 4 hrs

S = S1 + S2 + S3 = 2 + 18 + 55 = 75 km

V = S / T = 75 km / 4 hrs = 18.75 km/hr for the average speed

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