Question 891191
A biker travels from his house at an average speed of 30 kilometers per hour. He gets a flat tire and walks home, using the same route, at an average of 10 kilometers per hour. If it took him a total of 40 minutes for the entire trip, then how far did the cyclist travel from his house before he got a flat tire? 
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Avg speed for the round trip = 2*30*10/(30+10) = 600/40 = 15 km/hr
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15 km/hr * (2/3) hour = 10 km RT
= 5 km each way