SOLUTION: Running at an average rate of 8 m/s, a sprinter ran to the end of a track and then jogged back to the starting point at an average rate of 3 m/s. The sprinter took 55 s to run to t
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Question 972951: Running at an average rate of 8 m/s, a sprinter ran to the end of a track and then jogged back to the starting point at an average rate of 3 m/s. The sprinter took 55 s to run to the end of the track and jog back. Find the length of the track Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Running at an average rate of 8 m/s, a sprinter ran to the end of a track and then jogged back to the starting point at an average rate of 3 m/s.
The sprinter took 55 s to run to the end of the track and jog back.
Find the length of the track
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let d = the length of the track in meters
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Write a time equation. time = dist/speed
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run time + jog back time = 55 sec } + = 55
multiply equation by the least common multiple of 8 and 3
24*} + 24* = 24(55)
cancel the denominators
3d + 8d = 1320
11d = 1320
d = 1320/11
d = 120 meters is the length of the track
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;
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Confirm this by finding the actual time each way
120/8 = 15 sec
120/3 = 40 sec
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tot time: 55 sec
