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Alicia’s average speed riding her bike is 12 miles per hour. She goes from her house in a straight line against the wind to the beach, and then in a straight line with the wind back to her house, totaling 40 miles in 4 hours. What is the speed of the wind?

1 Answer

6 votes

Speed of wind is 4.90 miles per hour

Step-by-step explanation:

Let the speed of wind be w.

Alicia’s average speed riding her bike = 12 mph

Speed against wind = 12 - w

Speed with wind = 12 + w

Total distance traveled = 40 miles

Total time taken = 4 hours

Distance to beach is half of the distance traveled which is 20 miles

We have


(20)/(12-w)+(20)/(12+w)=4\\\\(5)/(12-w)+(5)/(12+w)=1\\\\60+5w+60-5w=144-w^2\\\\w^2=24\\\\w=4.90mph

Speed of wind is 4.90 miles per hour

User CamilleB
by
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