A train when moves at an average speed of 40 kmph, reaches its destination on time. When its average speed becomes 35 kmph, then it reaches its destination 15 minutes late. Find the length of the journey Select the correct option.
A) 40km B) 50km C) 60km D) 70km E) 80km
Difference between timings = 15 min =0.25hr.   Let the length of journey be x km.   Then,   x/35-x/40=0.25   8x - 7x = 70   x = 70km.   ANSWER:70km
<result>D</result>
A train when moves at an average speed of 40 kmph, reaches its destination on time. When its average speed becomes 35 kmph, then it reaches its destination 15 minutes late. Find the length of the journey