Question

a train covered a certain distance at uniform rate on increasing its speed by 5 km per hour it saves 20 minutes and on increasing its speed by 20 km per hour it loses 2 hours find the distance covered by the train​

Answer 1

Answer:

Let the speed of train be u. Let the train travels S km in time t

So ,

We know that

speed = \frac{distance}{time} \\ \\ u = \frac{s}{t} \\ \\ s = ut \\ \\  

According to first condition;

if it's speed increase by 5 km per hour it saves 20 minutes or 1/3 hour

s = (u+5)(t-1/3) \\ \\ 3ut = (u+5)(3t-1) \\ \\ 3ut = 3ut - u + 15t - 5 \\ \\ u - 15t = -5 \\ \\ 15t - u = 5  

Step-by-step explanation: