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3 years ago

Compute the average speed in m/s of a runner who completes a mile in 4.00min

2 answers:

5 0

You are incorrect

1 mile=1609.34 metres
1 minute=60 seconds
4 minutes=240 seconds
1609.34/240=6.705583333

so the answer is 6.71 m/s (3 s.f)

Mandarinka [93]3 years ago

3 0

   (1 mile / 4 min) x (1,609.344 meters/ 1 mile) x (1 min / 60 sec)

   = (1 x 1,609.344 x 1) / (4 x 1 x 60) m/s

   = 6.7056 m/s .

___________________________________

   (0.0041667 meter/sec) x (1 mile / 1,609.344 meters) x (60 sec / min)

   = (0.0041667 x 1 x 60) / (1 x 1,609.344 x 1) mile/min

   = 0.0001553... mile per minute

   = 0.0006214... mile in 4 minutes
_________________________________________

1 mile per hour = about 0.447 meter per second

1 meter per second = about 2.237 miles per hour

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