A bullet train leaves Kyoto for Tokyo traveling 240 miles per hour at 12 noon. Ten minutes later, a train leaves Tokyo for Kyoto traveling 160 miles per hour. If Tokyo and Kyoto are 300 miles apart, at what time will the trains pass each other?
!)Train K starts from Kyoto at 12:00 noon. It moves at the speed of 240 mph. Say it covers 300-x miles
2)Train T starts from Tokyo at 12:10 PM at a speed of 160 mph. Say it covers the rest of x miles
From (1) we have 300-x = 240(t+1/6) [ we have "+1/6" here since Train K travels 10 minutes or 1/6 hours longer than train T]
and From (2) we have x=160t
combining above two equations:
300-160t=240t + 40
260 = 400t
t= 26/40 = 13/20 hours = (13/20)*60 = 39 mins.
12:10 + :39 = 12:49
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