SOLUTION: Susan and Mary working together can rake the lawn in 2 hours. Susan can do the job alone in 3 hours. How long would it take Mary to rake the lawn alone?

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Question 31569: Susan and Mary working together can rake the lawn in 2 hours.
Susan can do the job alone in 3 hours.
How long would it take Mary to rake the lawn alone?
Answer by Paul(988) About Me  (Show Source):
You can put this solution on YOUR website!
let mary's rate be x
Equation:
1%2F3%2B1%2Fx=1%2F2
Multiply the whole equation by 6 to remove the fractions and simplify:
2%2B6%2Fx=3
6=3x-2x
x=6
Hence, it would take her 6 hours to do it alone.
Paul.