A train passes a 50 metres long platform in 14 seconds and

A train passes a 50 metres long platform in 14 seconds and a man standing on the platform in 10 seconds.The speed of the train is :

Rule 10 and Rule 1,
Let the length of train be x metres
∴ According to question

Speed of the train =	x	m/sec.
	10

Also, the speed of the train

=		x + 50		m/sec.
		14

[∵ It passes the platform in 14 seconds]
Both the speeds should be equal,
i.e.,

x	=	x + 50
10	=	14

or 14x = 10x + 500
or 14x – 10x = 500
or 4x = 500
∴ x = 125 metres

Hence, Speed =	125	= 12 5. m/sec.
	10

=	12.5 × 18	km/hr.
	5

= 45 km/hr.