The boat sails along the river at a speed of 10.5 km / h, and against the stream – 6.7 km / h.

The boat sails along the river at a speed of 10.5 km / h, and against the stream – 6.7 km / h. Find the current speed and the boat’s own speed.

Let’s calculate twice the speed of the river:
10.5 – 6.7 = 3.8 km / h – double the speed of the river.
Let’s calculate the speed of the river flow:
3.8: 2 = 1.9 km / h – river flow speed.
Let’s calculate the boat’s own speed:
10.5 – 1.9 = 8.6 km / h – the boat’s own speed.
Answer: the speed of the river is one point nine kilometers per hour, the boat’s own speed is eight point six kilometers per hour.