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A man is driving South to Florida for a vacation. On the way, he realizes that he needs a haircut, so he stops in a small town along the way. He asks one of the residents where he can find a barbershop, and the resident tells him that there are only two barbers in town, one in the north part of town and one in the south. The man visits the north barber, and finds that the barbershop is messy and the barber himself has a bad haircut. He then visits the south barber, who has a clean barbershop and a good haircut.
However, the man decides to return to the north barber for his haircut. Why does he do this?
This is why he does so!
Here is the question!
Since there are only 2 barbershops in town each barber has to go to each other for their haircut. So barber with good haircut must had it from the other barber at the north. Obviously, the man choose him to get a nice look.
Suppose distance between SECUNDERABAD & CST is 1000 KM. Railway tracks are in straight lines with no curves in between.
A train with uniform speed of 100 kmph departs from CST at 9:00 AM. Same day on same track other train from SECUNDERABAD departs at 10:00 AM with uniform speed of 80 kmph.
A bird sitting on engine of train that departed from CST starts traveling toward the SECUNDERABAD & after touching the engine of that train travels back to CST train. A bird repeats this until trains collide.
How much distance the bird traveled & how many times did it travel to & fro?
Click for the answer!
Here is the question!
Let's divide answer in 2 parts.
1.Finding distance traveled by the bird.
The SECUNDERABAD train is one hour late till then CST train covers 100 km.
Hence effective distance is 900 km
Total speed of approach = 100 + 80 kmph
Total distance covered = 900 km
Time passed before trains collide = 900/180 = 5 Hours
Speed of bird = 120 kmph
Distance covered in 5 hours by bird = 120 * 5 = 600 km
Distance covered in first hour by bird = 120 km
Total distance = 600 + 120 = 720 km
2. Finding how many times bird traveled back & forth.
1st travel -
Total speed of approach = 120 + 80 = 200 kmph
Total distance to be covered = 900 km
Time required to meet each other = 900/200 = 4.5 Hours.
2nd travel -
Distance traveled by CST train in 4.5 hours = 100 x 4.5 = 450km
Distance traveled by SECUNDERABAD train in 4.5 hours = 80 x 4.5 = 360 km
Distance between 2 trains = 900 - (450+360) = 90 km
Time left for collision is 5 - 4.5 = 0.5 hrs.
So bird ends up with 1 complete round.
