One genius said that geniality is a snap, you read about phrases and personalities is one of the things that I give value, is like music art, visit galleries, museums, theatres, and read about personalities that mark the Era. So think about something be easy, snap means geniality that, isn't easy for a common person when a genius explain everything came easy before is hard, geniality is do the same faster, better, inovting.
A man has to cross a train bridge on foot. After walking 1/3 of the length of the bridge, he sees a train coming towards him. Running both forwards and backwards at the same speed of 15 km/h, he manages to escape at the last moment before being crushed by the train. The speed of the train is?
A) 45 km/h
B) 60 km/h
C) 15 km/h
D) 30 km/h
For the solution you conclude with me is the man got save by hair string, so the time of the man and train is the same and the distance of the man if S of the train is 3S, why 3S because to practically reach the man the man was in 1/3 of the bridge running int the same direction and sentido of the train but the train gonna make all the bridge the 1/3 of the space that the man run and the 2/3 of distance that had between the 2.
so to the solution:
Vm = S/t and I already know that Vm = 15Kh/h
and for the train the Vt = 3S/t
So lets explicitly Vt = 3 (S/t)
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