Motor-cyclist P started his journey at a speed of 30 km/hr.

Motor-cyclist P started his journey at a speed of 30 km/hr. After 30 minutes, motor-cyclist Q
started from the same place but with a speed of 40 km/hr. How much time (in hours) will Q take to overtake P ?

Distance covered by motor cyclist P in 30 minutes

= 30 ×	1	= 15 km
	2

Relative speed
= 40 – 30 = 10 kmph
∴ Required speed = Time taken to cover is km at 10 kmph

=	15	=	3	hour
	10		2