Question 366404
John and Jim are going on a bike ride. On the trip to mill park, they ride at an average of 8 mph on a route that is 4 miles less than the route on the return trip. They travel 7 mph on the return trip. If it takes them 1hour longer to return than to go, how much total time do they spend riding their bikes?
return trip distance be x miles
forward distance to mill park ---- x-4 miles
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speed to mill park = 8 mph
return speed = 7 mph
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 return time -time to go to mill park  = 1 hour
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t=d/r
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x/7-(x-4)/8 =1
(8x-7(x-4))/56=1
8x-7x+28=56
x=56-28
x=28 miles return distance
forward distance = 28-4 = 24 miles
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t= d/r
28/7  + 24/8 = 7 hours
so They spend 7 hours riding
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m.ananth@hotmail.ca