SOLUTION: Two persons 27 km apart starting at the same time are together in 9 hours if they walk in the same direction but 3 hours if they walk in opposite directions. Find out speed of each

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Question 1014913: Two persons 27 km apart starting at the same time are together in 9 hours if they walk in the same direction but 3 hours if they walk in opposite directions. Find out speed of each man.
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
Use the formula d = r*t.
Let the rate of the first person be r%5B1%5D, and that of the second, r%5B2%5D
Then in the first scenario, we have 9r%5B1%5D+=+27+%2B9r%5B2%5D, or r%5B1%5D+=+3+%2Br%5B2%5D (Equation 1)
In the second scenario, we get 3r%5B1%5D+%2B+3r%5B2%5D+=+27, or r%5B1%5D+%2B+r%5B2%5D+=+9 (Equation 2)
Substituting equation 1 into equation 2, we get 3+%2B+r%5B2%5D+%2B+r%5B2%5D+=+9, or r%5B2%5D+=+3kph. Thus r%5B1%5D+=+6kph.