Question

a train travelling at a uniform speed passes by platform 220 metre long in 30 second and another platform 325 metre long in 39 seconds find the length of the train and the speed of the train​

Answer 1

Answer:

let the length of train be x

case 1st

Length of first platform=220m

total distance=(x+220)m

speed=Distance/Time

speed=(x+220)/30 .....eq(1)

Case 2nd

Length of second platform=325m

Total distance=(325+x)

Time=39 sec

speed=(325+x)/39 ....eq(2)

Equating eq.1&2

=> (x+220)/30 = (x+325)/39

=> (x+220)/10 = (x+325)/13

cross multiple

=> 13x + 220×13 = 3250 + 10x

=> 13x-10x = 3250-2860

=> 3x = 390

=> x = 130

Length of Train x = 130

put the value of x on eq.1

=> (x+220)/30

=> (130+220)/30

=> 350/30

=> 11.666 m/sec²