5 skilled workers can build a wall in 20days: 8 semi-skilled workers can build a wall
in 25 days; 10 unskilled workers can build a wall in 30days. If a team has 2 skilled, 6
semi-skilled and 5 unskilled workers, how long will it take to build the wall?

• let skilled worker 1 day work = x
  semiskilled worker 1 day work = y
  unskilled worker 1 day work = z
  5 skilled worker 1 day work = 5x
  5x=1/20
  =>x=1/100
  8 semiskilled worker 1 day work = 8y
  8y=1/25
  =>y=1/200
  10 unskilled worker 1 day work = 10z
  10z=1/30
  =>z=1/300
  a/c to ques, 2/100 + 6/200 + 5/300
  =>(12+18+10)/600
  =>1/15
  ans is 15 days
  
  
• 10 years agoHelpfull: Yes(12) No(0)
• 5 skilled workers can build a wall in 20days
  
  => 1 skilled worker can build a wall in 20 * 5 = 100 days
  
  => 1 skilled worker can complete 1/100 th of work in one day
  
  8 semi-skilled workers can build a wall in 25days
  => 1 semi-skilled worker can build a wall in 25 * 8 = 200 days
  => 1 semi-skilled worker can complete 1/200 th of work in one day
  
  10 un-skilled workers can build a wall in 30days
  => 1 un-skilled worker can build a wall in 30 * 10 = 300 days
  => 1 un-skilled worker can complete 1/300 th of work in one day
  
  Given that a team has 2 skilled, 6 semi-skilled and 5 unskilled workers:
  2 skilled can complete 2 * (1/100)th of work in one day => 1/50th
  6 semi-skilled can complete 6 * (1/200)th of work in one day => 3/100th
  5 un-skilled can complete 5 * (1/300)th of work in one day => 1/60th
  The team can complete => 1/50 + 3/100 + 1/60 = (6+9+5)/300
  = 20/300 = 1/15th of work in one day
  This means team can complete the work in 15 days
  
• 7 years agoHelpfull: Yes(0) No(0)