Question

A cow was standing on a bridge, 5m away from the middle of the bridge. A train was coming towards the bridge from the ends nearest to the cow. Seeing this cow ran towards the the train and managed to escape when the train was 2m away from bridge. If it had run in the opposite direction, it would hit by the train 2m before the end of the bridge. What is the lenght of the bridge in meters assuming the speed of the train is 4 times that of cow ?

Answer 1

Answer:

32 m

Step-by-step explanation:

Let say Bridge Length = 2B m

& Ignoring Cow Length

Cow Speed = C m/s

Train Speed = 4C m/s  ( 4 times)

Let say in T sec Cow escaped

Ditsnce Covered by Cow = CT

CT = B - 5  m

Train travelled = 4CT = 4(B - 5) = 4B - 20

Distance between Train & Cow = 4CT + 2 + B - 5 = 4CT + B - 3 = 4B - 20 + B -3 = 5B - 23 m

Let say after a min Train hot cow

Distnace covered by Cow = Ca = B+5 -2 = B + 3 m

Distance Covered by Train = 4Ca = 4(B + 3) = 4B + 12 m

Distance Covered by Train = Distance between Train & Cow  + Distnace covered by Cow

4B + 12 = 5B - 23 + B + 3

=> 32 = 2B

Length of Bridge = 2B =  32 m