there r 2 groups of worker.. skilled n partially skilled. if both group work togather they nid 30 days to finish the job. if partially skilled worker can oni do 2/3 of the skilled worker did in a day. how many days needed if only partially skilled worker is workin to finish the job?9 P5 |) t0 z( D
A.50: D& q( T( C# y, `
B.60
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D.75 |
發表於 2007-9-11 07:38 PM
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