A train passes two people walking in the same direction as the train at speeds of 2 and 4 kilometres per hour, passing them entirely in 9 and 10 seconds, respectively. The train is the following length
A. 45 m
B. 50 m
C. 54 m
D. 72 m
Answer:B
A train passes two people walking in the same direction as the train at speeds of 2 and 4 kilometres per hour, passing them entirely in 9 and 10 seconds, respectively. The train is the following length
A. 45 m B. 50 m C. 54 m D. 72 m
Explanation: 2 x 5/18 )m/sec = 5/9 m/sec) = 2 kmph,( 4 x 5/18 ) m/sec = 10/9 m/sec) = 4 kmph Let the train's length be x metres and its speed be y metres per second.Then (x/y -5/9) equals 9 and (x/y -10/9) equals 10.As a result, 9y minus 5 equals x, and 10(9y minus 10) equals 9x.=> 90y - 9x = 100 and 9y - x = 5.When we solve the problem, we get x = 50.As a result, the train's length is 50 metres.