Correct Option: B

Let speed of boat in still water = p kmph
and speed of current = q kmph

∴	24	+	36	= 6........(i)
	p - q		p + q

and	24	+	36	=	13	........(ii)
	p + q		p - q		2

By equation (i) × 2 – equation (ii) × 3, we have

48	-	108	= 12 -	39
p - q		p + q		2

⇒	60	=	15
	p - q		2

⇒ p – q = 8 ...... (iii)
By equation (i) × 3 – equation (ii) × 2, we have

108	-	48	= 18 - 13
p + q		p + q

⇒	60	= 5
	p + q

⇒ p + q = 12 ..... (iv)
From equation (iv) – (iii),
we have , ( p + q ) – ( p - q ) = 12 – 8
⇒ p + q – p + q = 12 – 8
⇒ 2q = 4 ⇒ q = 2 kmph