By Anonymous on Thursday, May 17, 2001 - 07:28 am:
A ship goes in one direction, west to Hawaii, at 20 nautical
mile per hour and, because of the wind, makes the return trip at 30
nautical miles per hour. What is its average speed?
Some detailed explanation of the solution would be very helpful and
much appeciated...thanks in advance!
By Michael Doré (Md285) on Thursday, May 17, 2001 - 11:55 pm:
If the distance to Hawaii is x (in nautical miles) then the total time taken is x/20 + x/30. Now the average speed = total distance/total time = 2x/(x/20 + x/30). I'll leave you to simplify this.
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