A boat can travel 60 km in 3 hours while going downstream, It can travel 90 km in 5 hours while going upstream. What is the ratio of the speed of the boat in still water to the speed of the stream?

19 : 1

Given,

A boat can travel 60 km in 3 hours while going downstream, It can travel 90 km in 5 hours while going upstream

Speed of the boat in downstream = \(\frac{60}{3}\)= 20 km/hour

= Speed of the boat in upstream = \(\frac{90}{5}\)= 18 km/hour

= Speed of the boat = \(\frac{20 + 18}{2}\)= 19 km/hour

= Speed of the stream = \(\frac{20 - 18}{2}\)= 1 km/hour

= Speed of the boat : Speed of the stream = 19 : 1