A and B can do a piece of work in 12 days.B and C can do a work in 15 days.if A is twice as good a workman as C.find in what will B alone do it?

• 1/A+1/B=1/12
  1/B+1/C=1/15
  AND 1/A=2/C
  So, B=20DAYS
• 10 years agoHelpfull: Yes(2) No(2)
• (A+B)'s 1day work=1/12
  (B+c)'s 1day work=1/15
  Take,A's 1 day work =x
  then c's 1 day work=x/2
  so x+B(1 day work)=1/12
  B=1/12 -x
  1/12-x+(x/2)=(1/15)[B's 1 day work + C's 1 day work =1/15]
  so x=1/30(B's 1 day work)
  put this value in B's 1 day work
  you will get 1/15
  so B alone will complete work in 15 days.
  
• 10 years agoHelpfull: Yes(1) No(2)
• answer is 60 because from question we get thata=c/2
  1/a+1/b=1/12 and 1/b+1/c=1/15 we get b=c/3 now adding above two equn we get 1/a+1/b+1/b+1/c=1/12+1/15 hence b=60
• 10 years agoHelpfull: Yes(0) No(0)
• 1/A+1/B=1/12
  1/B+1/C=1/15
  AND 1/A=2/C
  So, B=20DAYS
• 10 years agoHelpfull: Yes(0) No(0)