2013 AMC 8 Problems/Problem 7
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[hide]Problem
Trey and his mom stopped at a railroad crossing to let a train pass. As the train began to pass, Trey counted 6 cars in the first 10 seconds. It took the train 2 minutes and 45 seconds to clear the crossing at a constant speed. Which of the following was the most likely number of cars in the train?
Solution 1
Clearly, for every seconds, cars pass. It's more convenient to have everything in seconds: minutes and seconds seconds. We then set up a ratio:
~megaboy6679 ~MiracleMaths
Solution 2
minutes and seconds is equal to .
Since cars pass at around seconds, there are about groups of cars. There are about , so the closest answer choice is .
Video Solution
https://www.youtube.com/watch?v=7avOfjhUT6Q ~David
https://youtu.be/79lJItxCt50 ~savannahsolver
See Also
2013 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 6 |
Followed by Problem 8 | |
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All AJHSME/AMC 8 Problems and Solutions |
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