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2015 ASDAN Math Tournament
24
24
Part of
2015 ASDAN Math Tournament
Problems
(1)
2015 Guts #24
Source:
7/28/2022
Trains
A
A
A
and
B
B
B
are on the same track a distance
100
100
100
miles apart heading towards one another, each at a speed of
50
50
50
miles per hour. A fly starting out at the front of train
A
A
A
flies towards train
B
B
B
at a speed of
75
75
75
miles per hour. Upon reaching train
B
B
B
, the fly turns around and flies towards train
A
A
A
, again at
75
75
75
miles per hour. The fly continues flying back and forth between the two trains at
75
75
75
miles per hour until the two trains hit each other. How many minutes does the fly spend closer to train
A
A
A
than to train
B
B
B
before getting squashed?
2015
Guts Test