SOLUTION: to a certain job A takes three times as long as B takes. if both of them working together take 9 days, how many days will a take to finish the job working alone?

Question 760048: to a certain job A takes three times as long as B takes. if both of them working together take 9 days, how many days will a take to finish the job working alone?
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Let A's rate of working =
B works 3 times faster, so
B's rate of working =
Their rate working together is ( 1 job ) / ( 9 days )
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If you add their rates of working, you get
their rate working together

Working alone, A will finish the job in 36 days
check:

OK

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