Work left

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Work left

by maihuna » Thu May 07, 2009 5:34 am
A B and C can complete a work separately in 24 36 and 48 days respectively. They started together but C left after 4 days of start and A left 3 days before the completion of thw work. In how many days the work will be completed:

15
22
25
35
41
Source: — Problem Solving |

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by scoobydooby » Thu May 07, 2009 5:45 am
i get 15

in 4 days A, B, C complete 4*(1/24+1/36+1/48)=13/36 of the work
work left: 23/36

let A work for d-3 days after the 1st 4 days, let B work for d days aftre the 1st 4 days

(d-3)/24+d/36=23/36
=>(60d-108)/36*24=23/36
=>d=11

total number of days taken: 4 days+ 11 days (after C left)=15 days.