SOLUTION: You drive at an average of 30 miles per hour on the way to work, and at an average of 35 miles per hour on the way home. The total driving time is 30 minutes. How far away is work?
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Question 1091722: You drive at an average of 30 miles per hour on the way to work, and at an average of 35 miles per hour on the way home. The total driving time is 30 minutes. How far away is work? Round your answer to the nearest hundredth of a mile.
You can put this solution on YOUR website! You drive at an average of 30 miles per hour on the way to work, and at an average of 35 miles per hour on the way home. The total driving time is 30 minutes. How far away is work? Round your answer to the nearest hundredth of a mile.
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Avg speed of a round-trip = 2*r1*r2/(r1+r2)
= 2*20*35/(30+35) = 1400/65 = 280/13 mi/hr
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d = r*t = (280/13)*(1/2) = 140/13 miles
