SOLUTION: A and B take 18 days to complete a piece of work .A left the work after 10 days and B takes 12 days more to complete the work.In how many A can complete the whole work?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: A and B take 18 days to complete a piece of work .A left the work after 10 days and B takes 12 days more to complete the work.In how many A can complete the whole work?      Log On


   

Question 1064288: A and B take 18 days to complete a piece of work .A left the work after 10 days and B takes 12 days more to complete the work.In how many A can complete the whole work?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
If A and B are their individual rates in WORK per DAYS, then this system describes the situation:

system%28%28A%2BB%2918=1%2C%28A%2BB%29%2A10%2BB%2A12=1%29

SIMPLFICATIONS

18A+18B=1
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10A+10B+12B=1
10A+22B=1
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system%2818A%2B18B=1%2C10A%2B22B=1%29
Solve this system for A and B, but you will want the reciprocal of A, if the question you want is, how much time does "A" need alone to do one piece of work.