a motorboat left a harbor and traveled to an island at an average rate of 12 knots, the average speed on the return trip was 10 knots. If the total trip took 8.8 hours, how far is the harbor from the island?

Answer 1

let the distance be x nautical miles

x/12 + x/10 = 8.8
times 60
5x + 6x = 528
x = 48 n miles.

check:
one way = 48/12 = 4 hrs
other way = 48/10 = 4.8 , for a total of 8.8 hrs