Question

A passenger train takes 2 hours less for a journey of 300 km if its speed is increased by 5km/hr from its usal speed find its usal speed

Answer 1

Answer:

100

Explanation:

distance= 300

time =5

less than 2 hours=5-2

=3 hours

$speed \ \times \frac{distance}{time}$

speed=300÷3

=100

Answer 2

Answer:

Let the usual speed of the train be y km / hr .

A.T.Q.

$\displaystyle{\frac{300}{y} -\frac{300}{y+5} =2 }$

300 ( y + 5 ) - 300 y = 2 y ( y + 5 )

y² + 5 y - 750 = 0

y² + 30 y - 25 y - 750 = 0

( y + 30 ( y -25 ) = 0

y = - 30 or y = 25

Since , speed of train can't be negative .

Therefore , the usual speed of the train is 25 km / hr .