3 friends A,B,c went for week end party ti Mc donald resturent and there they measure there weights in some order IN 7 rounds.
A,B,C,AB,BC,AC,ABC. final round measure is 155kgthen find average weight of all the 7 rounds.

• A+B+C= 155 kg
  
  Average of 7 rounds = (A+B+C+A+B+A+C+B+C+A+B+C)/7 = 4*(A+B+C)/7 = 4*155/7 = 620/7 kg
  
• 12 years agoHelpfull: Yes(16) No(0)
• They Measure their weights 1 by 1....
  then they measure it together....
  So we can for equation like this
  =A+B+C+(A+B)+(B+C)+(A+C)+(A+B+C)
  =(A+B+C)+(A+B+C)+(A+B+C)+(A+B+C)
  =4(A+B+C)
  And final measure is 155Kg. ie (A+B+C)=155kg
  So, 4x155=620
  Hence the avg is 620/7=88.571428 Kg.
  Ans is 88.571428kg
• 12 years agoHelpfull: Yes(1) No(0)
• 88.57
  if last measure is 155 tht means ABC=155
  so A+B+C= 155 (1st 3 measures)
  nxt cmg to AB,BC,AC = 155*2 (since A,B,C occurs 2 tyms)
  finally avg=(155+155+155*2)/7 = (155*4)/7 =88.57
• 12 years agoHelpfull: Yes(1) No(1)
• the ans is
  155*4/7
• 12 years agoHelpfull: Yes(0) No(0)
• 
  A+B+C+(A+B)+(B+C)+(A+C)+(A+B+C)
  =(A+B+C)+(A+B+C)+(A+B+C)+(A+B+C)
  =4(A+B+C)
  And final measure is 155Kg. ie (A+B+C)=155kg
  So, 4x155=620
  Hence the avg is 620/7=88.571428 Kg.
  Ans is 88.571428kg
• 12 years agoHelpfull: Yes(0) No(0)