Question

A train travels a distance of 300 km at a uniform speed if the speed of the train is increased by 5 km an hour,the journey would have taken 2 hour less find the original speed of the train

Answer 1

Let the original speed of train = X km/hr

Distance=300 km

Speed= Distance / Time

300/X -300/ X+5 =2

300 X -300 X+ 1500=2 X^2 + 10 X

2 X^2 +10 X -1500 = 0

X ^ 2+ 5 X - 750= 0

BY MIDDLE TERM FACTORISATION

X= 25 Km/hr

ANSWER IS 25 KM/HR