<PRE><B>Question 338715</B>
A car is moving with 30 km/h, and passes the distance between A and B 54 minutes
 faster than a bicycle that runs with 12 km/h.
 What is the distance between A and B?
:
Let d = the distance from A to B
:
Change 54 min to .9 hrs
:
Write a time equation, Time = dist/speed
:
Car time + .9 hr = Bike time
{{{d/30}}} + .9 = {{{d/12}}}
multiply by 60 to get rid of the denominators, results:
2d + 60(.9) = 5d
54 = 5d - 2d
54 = 3d
d = {{{54/3}}}
d = 18 km is the distance from A to B
:
:
Check the solution by finding the travel time of each
18/12 = 1.5 hr
18/30 = 0.6 hrs
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differ: .9 hr which is 54 min
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