A journey takes 4 hours 30 minutes at a speed of 60 km/hr.

A journey takes 4 hours 30 minutes at a speed of 60 km/hr. If the speed is 15 m/s, then the
journey will take

60 kmph =		60 × 5		m/sec
		18

=	50	m/sec.
	3

∴ Speed ∝	1
	Time

⇒ S₁ × T₁ = S₂ × T₂

⇒	50	×	9	= 15 × T₂
	3		2

⇒ T₂ =	75	= 5 hours
	15

Second Method :

Here, S₁ = 60, t₁ = 4	1	=	9
	2		2

S₂ = 15 ×	18	= 54
	5

S₁t₁ = S₂t₂

60 ×	9	= 54 × t₂
	2

t₂ =	270	= 5 hours
	54