# The boat sails some distance downstream in 3 hours and also the distance upstream of the river in 4 hours

August 23, 2021 | education

| **The boat sails some distance downstream in 3 hours and also the distance upstream of the river in 4 hours, determine your own speed if the speed of the river flow is 3 km / h what distance the boat traveled**

Let x be the boat’s own speed, then (x + 3) is its speed downstream, and (x – 3) is its speed upstream. Since the boat sailed the same distance upstream and upstream, we will compose and solve the equation:

3 (x + 3) = 4 (x – 3),

3x + 9 = 4x – 12,

3x – 4x = – 12 – 9,

– x = – 21,

x = 21. The boat’s own speed is 21 km / h.

Let’s find the distance traveled by the boat downstream:

3 (21 + 3) = 3 * 24 = 72 km.

The same distance traveled against the current, which means that the boat sailed in total:

72 * 2 = 144 km.