SOLUTION: a horse galloped a mile in 2 min 35 s.. what was its average speed in km/h? i dont know how to figure this out!!

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Question 939739: a horse galloped a mile in 2 min 35 s.. what was its average speed in km/h? i dont know how to figure this out!!
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
The work needs some unit conversions. The time given is already in mixed units, so this takes a bit of work on its own. Do that conversion FIRST just for comfort. Use unit conversions in the form of fractions, and KEEP each unit with its value.


How many hours is 2 minutes 35 seconds?



2%2F%2860%29%2B35%2F3600, unit of HOUR

%282%2F60%29%2860%2F60%29%2B35%2F3600, because need common denominator

%28120%2B35%29%2F3600

155%2F3600, HOUR

Reduced to highlight_green%2831%2F720%29 HOUR.


You want now to know how to change 1 mile into how many kilometers. The conversions you can use are these:
1 mile =5280 feet
1 foot = 12 inches
2.54 centimeters = 1 inch
100 centimeters = 1 meter
1 kilometer = 1000 meters

You should be able to do the rest and to finish.