Question

A bus covers its journey at the speed of 80km/hr in 10hours. If the same distance is to be covered in 4 hours, by how much the speed of bus will have to increase ?
A) 85 km/hr
B) 95 km/hr
C) 105 km/hr
D) 120 km/hr

Answer 1

v = 80km/h ____(i)
t = 10h
distance = 80×10 = 800km

given, now
v = x
t = 4h
distance = 800km

Speed = distance / time
x = 800/4 = 200km/h

Now,
Speed required = 200-(i)
= 200-80
= 120km/h....