A can do a job in 10 days.B can do the same job in 15 days.C can demolish the same job in 20 days.In how many days does the work get completed, if C starts the work and they work alternate days as C-A-B-C and so on.

• A's one day work = 1/10
  B's one day work = 1/15
  and c's demolish in one day = -1/20 negative the work is destructed
  so for every three days work done is = add of all three
  i.e 7/60
  work done for 24 days(excluding c's first day work where nothing is there to demolish) = 56/60
  A will do 4 units in 2/3 days
  
  Total days required=24+2/3+1(first day of job)=25+2/3 days
• 11 years agoHelpfull: Yes(1) No(1)