Question 793952: Two men leave at the same time to walk from point A to points B. The distance between A and B is 30 kilometers. The 1st man arives to point B one hour before the 2nd man arrives there. We know that when the 1st man had traveled 12 kilometers, the 2nd man traveled 10 kilometers. What was the speed of both men?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Two men leave at the same time to walk from point A to points B. The distance between A and B is 30 kilometers. The 1st man arives to point B one hour before the 2nd man arrives there. We know that when the 1st man had traveled 12 kilometers, the 2nd man traveled 10 kilometers. What was the speed of both men?
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1st man DATA:
distance = 30 km ; time = x hrs ; rate 30/x km/hr
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2nd man DATA:
distance = 30 km ; time = x+1 hrs ; rate = 30/x+1 km/hr
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1st man data:
distance = 12 km ; rate = 30/x ; time = d/r = 12/(30/x) = 2x/5 hrs
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2nd man data:
distance = 10 km ; rate = 30/(x+1); time = 10/[30/(x+1)] = (x+1)/3 hrs
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Solve for "x":
2x/5 =(x+1)/3
6x = 5x+5
x = 5 hrs
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What was the speed of both men?
1st man rate = 30/x = 30/5 = 6 km/hr
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2nd man rate = 30/(x+1) = 30/6 = 5 km/hr
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Cheers,
Stan H.
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