aamir and birju can cut 5000 g of wood in 20 min.birju and charles can cut 5000 g of wood in 40 min.charles and aamir can cut 5 kg of wood in 30 min.how much time charles will take to cut 5 kg wood alone??

• 4 hours.
  
  Here quantity of cutting wood or work i.e. 5000 g or 5 kg is same. Let Aamir, Birju and Charles alone can complete the work in A, B and C minutes respectively, then
  1 min. work of (A+B)=1/20, (B+C)=1/40 and (C+A)=1/30
  Adding all we get 2(A+B+C)=1/20 + 1/40 + 1/30 = 13/120 or (A+B+C)=13/240
  1 min. work of C = (A+B+C) - (A+B) = 13/240 - 1/20 = 1/240
  So C alone can complete the work in 240 min. or 4 hrs.
• 6 years agoHelpfull: Yes(0) No(0)