Question 120616
A passenger train left Austin, Texas, at 12:00pm bound for Dallas, exactly 210 miles away; it traveled at a steady 50 miles per hour. At the same instant, a freight train left Dallas headed for Austin on the same track, traveling at 20 miles per hour. At this same high noon, a fly leaped from the nose of the passenger train and flew along the track at 100 miles per hour. When th efly touched the nose of the oncoming freight train, she turned and flew back along the track at 100 miles perhour toward the passenger train. When she reached the nose of the passenger train, she instatly turned and flew back toward the freight train. She continued turning and flying until, you guessed it, she was squashed as the trains collided head on. How far had the fly flown before her untimely demise?
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Find the time that it takes for the two trains to meet. Then multiply that by 100 mph, that's how far the fly flew.
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Let t = time required for the two trains to meet
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We know that when this happens, they will have traveled a total 210 min
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Write a distance equation Distance = Speed * time:
50t + 20t = 210
70t = 210
t = 210/70
t = 3 hrs
:
A fly flying at 100 mph for 3 hr travels 300 mi obviously