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S. Mikhelson
Brooklyn Friends US, 2006-2007, Algebra II – S
EXTRA CREDIT PROBLEM (September 12, 2006, homework 1)
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Fly problem. (3)
Two trains start towards each other at
the same time from cities A and B. The
distance between the cities is 300 miles.
Train traveling from city A makes 40
miles per hour, the one going from city
B makes 60 miles per hour.
A fly takes off the train going from city
A at the moment it starts the trip. The
insect makes 70 miles per hour and flies
until it meets the other train. Then it
turns back and hurries with the same
speed till it reaches the first train. After
that it returns to the train going in the
opposite direction. This process
continues until the trains meet.
How many miles will the poor fly cover
by that moment?