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Two tankers, one 240 m in length and the other 180 m in length, travel parallel to each other at different
but constant speeds. When traveling in opposite directions, it takes them 12 seconds to pass each other,
and when traveling in the same direction they take 60 seconds to pass each other.
Find the difference in their speeds, in metres/second.
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When they pass each other in the same direction, they should move 240 + 180 = 420 m
relative each other in 60 seconds.
So, their relative speed, or the speed "catching up" is then 420/60 = 7 meters per second.
The "catching up" speed is the difference of speeds, so we have this equation.
u - v = 7 m/s.
It means that the difference of their speed in the same direction is 7 m/s. ANSWER
Solved.