Two trains A and B starting from two points and travelling in opposite directions, reach their destinations 9 hours and 4 hours respectively after meeting each other. If the train A travels at 90kmph, find the rate at which the train B runs.  Select the correct option: A) 40 B) 60 C) 135 D) 80 E) 100
If two objects A and B start simultaneously from opposite points and, after meeting, reach their destinations in ‘a’ and ‘b’ hours respectively (i.e. A takes ‘a hrs’ to travel from the meeting point to his destination and B takes ‘b hrs’ to travel from the meeting point to his destination), then the ratio of their speeds is given by:   Sa/Sb = √(b/a)   i.e. Ratio of speeds is given by the square root of the inverse ratio of time taken.   Sa/Sb = √(4/9) = 2/3   This gives us that the ratio of the speed of A : speed of B as 2:3.   Since speed of A is 80 kmph, speed of B must be 80*(3/2) = 135 kmph   135
<result>C</result>
Two trains A and B starting from two points and travelling in opposite directions, reach their destinations 9 hours and 4 hours respectively after meeting each other. If the train A travels at 90kmph, find the rate at which the train B runs.