A boat covers 800 meters in 600 seconds against the stream and returns downstream in 5 minutes. What is the speed of the boat in still water?

2 m/sec

Upstream_speed = \(\frac{800 }{600 }\) = \(\frac{4 }{3 }\) m/s

Downstream_speed = \(\frac{800 }{300}\) = \(\frac{ 8}{3 }\) m/s

Let's assume x = speed of boat and y = speed of stream

Upstream_speed = x - y, whereas, downstream_speed = x + y

Adding Upstream_speed and downstream_speed, we get:

x - y = \(\frac{4 }{ 3}\)

x + y = \(\frac{ 8}{3 }\)

2x = \(\frac{4 }{ 3}\) + \(\frac{8 }{ 3}\)

2x = \(\frac{12 }{3 }\)

2x = 4

x = 2m/s