Question

The speed of an express train is 10 km/h slower than the speed of a superfast train. If the superfast
train takes 30 minutes to cover a distance of 80 km, find the time taken by the express train to cover
this distance. (answer will be: Speed of an express train is 150 km/h and time taken 32 minutes. take x as variable​

Answer 1

Answer:

32 minutes

Step-by-step explanation:

let speed of express train is v1 and speed of superfast train is v2.

hence, v1 = v2 - 10, km/h

also, distance = speed X time

thus, 80 = v2 x 0.5 .................. since time is 30 minutes i.e. 0.5 hr

thus, v2 = 80/0.5 = 160 km/h

thus, v1 = 160 - 10 = 150 km/h

thus, 80 = v1 x t1.............. t1 is time taken by express train to cover 80 km

thus, 80 = 150 x t1

thus, t1 = 80/150 hr

thus, t1 = (80/150) X 60 minutes

thus, t1 = 32 minutes