Been stuck on this problem and unsure how to complete.

A horse galloped a mile in 2 min 35 s. What was its average speed in km/h?

Any thoughts?

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- Jan 20th 2013, 05:37 PMdempsey1905Converting minutes and speed to km/hr.
Been stuck on this problem and unsure how to complete.

A horse galloped a mile in 2 min 35 s. What was its average speed in km/h?

Any thoughts? - Jan 20th 2013, 08:27 PMibduttRe: Converting minutes and speed to km/hr.
Horse gallops 1 mile in 2 min and 35 sec

We are to find speed in km/h

Let us first convert 2 min and 35 sec in hours

2 min and 35 sec = 2 min + 35/60 min = 2 min + 7/12 min = 31/12 min = 31/(12x 60) hours

Now the horse covers in 2 min 35 sec distance = 1 mile

i.e., the horse covers in 31/(12x 60) hours distance = 1 mile

Or the horse covers in 1 hours distance = 1 x [ (12x60)/31] mile

But 1 mile = 1.61 km

Thus the horse gallops [ 12x60/31 ] 1.61 km in 1 hour

That is the speed in km / h - Jan 20th 2013, 08:33 PMProve ItRe: Converting minutes and speed to km/hr.
For starters, 1 mile = 1.609344 kilometres. So set up a ratio of miles : seconds, we have

1 mile : 155 sec

1.609344 km : 155 sec

1.609344 / 155 km : 1 sec

(1.609344 / 155) * 3600 km : 3600 sec

37.37831 km : 1 hr

So it's about 37 km/h.