SOLUTION: Dan drove from his farm to town travelling the first 50km at 80 km/h, and the next 30km at 60km/h, he then returned home at 100km/h. what was his average speed for the whole trip?
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Question 1191128: Dan drove from his farm to town travelling the first 50km at 80 km/h, and the next 30km at 60km/h, he then returned home at 100km/h. what was his average speed for the whole trip? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! the whole trip was 80 km there and 80 km back for 160 km
It took him 5/8 of an hour to do the first part + 1/2 hour to do the second part going away.
It took him 8/10 of an hour to come home.
The total time is 5/8+1/2+4/5=(25+20+32)/40=77/40 hours to do 160 km; 77/40hr=160 km
multiply by the reciprocal, 40/77, and 1 hour he went 83.12 km
ave speed 83.12 km/h
