Question 556805: Two Trains start from two
opposite directions towards each
other. The stations from which
they start are 50 Kms apart from
each other. Both the trains start at
the same time. A Crow which is
sitting on one train starts at the
same time towards the other
train. As soon as it reaches the
second one, flies back to the first
train and then returns back to the
second one as soon as it reaches
the first train, and so on and so
forth. It continues to do so, flying
backwards and forwards from
one train to the other until the
trains meet.
Both the trains travel at a speed of
25 Kms per Hour, and the bird
flies at 100 Kms per hour.
How many Kms will the crow have
flown before the trains meet?
Answer by Theo(13342)   (Show Source):
You can put this solution on YOUR website! as far as i can tell, the answer is that the bird will have flown 100km.
here's why i think that is the answer.
the trains will take 1 hour to meet each other.
they will meet in the middle since both trains were traveling at the same speed.
the general formula is:
rate * time = distance
they are both traveling the same time, so time = T
train 1 travels a distance of d1
train 2 travels a distance of d2
the total distance is d, so we get d1 + d2 = d
when the trains meet, the sum of the distance they traveled is equal to d.
d is equal to 50
we get d1 + d2 = 50
the formula for the first train is:
25 * T = d1
the formula for the second train is:
25 * T = d2
since we know that d1 + d2 = 50, we can substitute for d1 and d2 to get:
25 * T + 25 * T = 50
combine like terms to get:
50*T = 50
divide both sides of equation by 50 to get:
T = 1
the trains will meet in 1 hour.
the bird is flying all the time.
it is either flying to one train or the other.
the bird flies at 100 km per hour for 1 hour so the bird has flown 100 km by the time the trains meet.
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