Question

4. a train travel a distance of 250km at a
uniform speed. if the speed had been 5 km
less, then it would have taken 5/2 hours
more to cover the same distance. find the
speed.​

Answer 1

Answer:

Let speed be x

T=360/x

If speed is increased by 5 km/h

speed will be (x+5)km/h

distance is the same

T= 360/(x+5)

time with original speed - time with increased speed = 1

360/x - 360/(x+5)=1

LCD= x(x+5)

(360(x+5)-360x) /x(x+5)=1

360x+1800-360x=x(x+5)

x^2+5x = 1800

x^2+5x-1800=0

x^2+45x-40x-1800=0

x(x+45)-40(x+45)=0

(x-40)(x+45)=0

x= 40 mph the original speed ,i;e speed of train is 40 mph