The motor boat moves against the river flow in 1.2 hours covered 7.8 km.

The motor boat moves against the river flow in 1.2 hours covered 7.8 km. What path will this boat take in 6 hours along the river, if the current speed is 1.7 km / hour.

Decision:
1) Find the boat’s own speed:
x km / h – own boat speed
Since the boat was moving against the current of the river:
(x-1.7) * 1.2 = 7.8
x-1.7 = 7.8 / 1.2
x-1.7 = 6.5
x = 6.5 + 1.7
x = 8.2
8.2 km / h – boat’s own speed
2) Let’s find how long the boat will pass along the river in 6 hours:
(8.2 + 1.7) * 6 = 9.9 * 6 = 59.4 km
Answer: 59.4 km