Question

A boat covers a distance of 14 km in 4 hours along the flow. What is the speed of the boat in still water, if the speed of the flow of water is 2 km/hr? 

(a) 2 km/hr 

(b) 3 km/hr 

(c) 2.5 km/hr 

(d) 1.5 km/hr

Answer 1

(d)   \(1\frac12\) km/hr

Speed of the flow of water = 2 km/hr 

Speed of the boat downstream = \(3\frac12\) km/hr 

Let the speed of the boat in still water = \(x\) km/hr 

Then, \(x\) + 2 = \(3\frac12\) ⇒ \(x\) = \(1\frac12\) km/hr.