A can do double work of B.so,A take 15 days less than B in doing a work.then both together in how much days will finish that work?
Choose the correct answer:  A) 10  B) 12  C) 15  D) 8  E) 16
let alone finish a work in x days.,then B will take 2x days   2x-x=15,x=15.   so,10 alone finish this work in 15 days and B alone finish this work in 30 days   work of 10 in 1 days=1/15,work of B in 1 days=1/30   (10+B) work in 1 days=1/10   so, together they finish the work in 10 days   answer 10
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A can do double work of B.so,A take 15 days less than B in doing a work.then both together in how much days will finish that work?