Problem:
Buses from Dallas to Houston leave every hour on the hour. Buses from Houston to Dallas leave every hour on the half hour. The trip from one city to the other takes hours. Assuming the buses travel on the same highway, how many Dallas-bound buses does a Houston-bound bus pass on the highway (not in the station)?
Answer Choices:
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Solution:
A Houston-bound bus leaving Dallas at p.m., for example, will arrive in Houston at p.m., having passed buses that left Houston at p.m., p.m., p.m., ..., p.m. That is buses.
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions