In 8 seconds, two trains, each 100 metres long and going in opposite directions, cross each other. If one train travels twice as fast as the other, the faster train's speed is:
A. 30 km/hr
B. 45 km/hr
C. 60 km/hr
D. 75 km/hr
Answer:C
In 8 seconds, two trains, each 100 metres long and going in opposite directions, cross each other. If one train travels twice as fast as the other, the faster train's speed is:
A. 30 km/hr B. 45 km/hr C. 60 km/hr D. 75 km/hr
Explanation: Let the slower train's speed be x m/sec.The faster train's speed is then 2x m/sec.(x + 2x) m/sec = 3x m/sec is the relative speed.3x (100 + 100)/8=200 divided by 24=25/3 is the value of x. As a result, the quicker train's speed is 50/3 m/sec.= 50/3 x 18/5 km/hr.60 km/hr is a speed of 60 km/hr.