SOLUTION: A motorboat left a harbor and traveled to an island at an average rate of 15 knots. The average speed on the return trip was 10 knots. If the total trip took 7.5 hours, how far is

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Question 161667: A motorboat left a harbor and traveled to an island at an average rate of 15 knots. The average speed on the return trip was 10 knots. If the total trip took 7.5 hours, how far is the harbor from the island?
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
D=RT
T=D/R
7.5=D/15+D/10
7.5=(10D+15D)/150
7.5=25D/150
25D=7.5*150
25D=1125
D=1125/25
D=45 MILES FROM THE HARBOR TO THE ISLAND.
PROOF:
7.5=45/15+45/10
7.5=3+4.5
7.5=7.5