Question 26165: A passenger train traveling at a steady 60 mph leaves a station in Washington D.C. at 12:00 noon bound for Boston, exactly 440 miles away. At the same instant a freight train traveling at 50 mph leaves Boston headed for Washington D.C. on the same track. At this same high noon a fly sitting on the nose of the passenger train flies straight down the track towards the freight train. When the fly reaches the freight train it immediately turns around without pausing and heads towards the other train. It continues to do this until the two trains collide and it is smashed. If the fly travels at a steady 80 mph, how many miles does the fly travel before it is smashed?
I have already figured out that halfway would be 220 miles, the passenger train would go 310 miles and the freight train would go 130 miles when they collide, I just am not sure if this is right and where the fly comes in. Please help!!!
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! The fly flies untill the trains meet. So you have to figure out
how long it took till the trains met.
Data for Wash. to Bos. train:
distance is "x"; rate is 60mph; time is distance/time = x/60
Data for Bos. to Wash. train:
distance is "440-x"; rate is 50mph; time is distance/time = (440-x)/50
EQUATION:
The times must be equal:
x/60 = (440-x)/50
Multiply by 10 to get:
x/6 = (440-x)/5
5x=6(440-x)
5x=2640-6x
11x=2640
x=240 miles (distance the Wash. to Bost. train traveled at 60mph)
240/60=4hr (time the Wash. to Bost. train took to meet the other train)
The fly flew for four hours at 80mph, so it flew 4(80)=320miles.
Cheers,
Stan H.
The trai
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