SKH121 wrote:
The Lirr River runs from Rosedale in the west to Oceanside in the east with the current moving at an average of 10 miles per hour.Sasha is traveling by motorboat from
Oceanside to Rosedale and back. If the water were not moving, Sasha’s motorboat would travel at an average speed of 20 miles per hour. Given the current, what was Sasha’s actual
average speed, in miles per hour, for the round trip?
If current is taken into consideration then,
Sasha's speed when moving towards oceanside will be 'S1' = 20 + 10 = 30m/hr
Sasha's speed when moving towards Rosedale will be 'S2'= 20 -10 = 10 m/hr
Now the Av speed for the whole trip = \(\frac{(2 * S1 * S2 )}{(S1+S2)}\) = 15 m/hr
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