The average weight of 8 persons increases by 2.5 kgs when a new person is placed in one of them weighting 65 kgs.what might be the weight of a new person?

• general formulae....
  value of added quantity =(change in avg*number of quantity )+value of removed quantity
  
  if change in avg is decreased take negative value else positive
  
  so ans 2.5*8+65=85
• 9 years agoHelpfull: Yes(8) No(0)
• Total weight increased-8*2.5=20kg
  Weight of new person=65+20=85kg
• 8 years agoHelpfull: Yes(4) No(0)
• 85kgs
  
  8(x+2.5)=8x-65+y
  solvg weight of new person y=85
• 9 years agoHelpfull: Yes(1) No(0)
• Total weight increase=2.5*8=20
  out going person weight =60
  then new person weight =60+20=85
• 9 years agoHelpfull: Yes(0) No(4)
• 2.5×8=20(every person increase 2.5) here increase 20kgs..weighting of 65 kgs 65+20=85
  
  
• 9 years agoHelpfull: Yes(0) No(0)
• 8*2.5+65=85
• 8 years agoHelpfull: Yes(0) No(0)
• Answer : 85kg
• 8 years agoHelpfull: Yes(0) No(0)
• Let solve in our understanding way:
  Let
  X/8=a. (X-total weight, a-average)
  By our condition let
  (X-65+n)/8=a+2.5
  By solving the above equations 'X' and 'a' are vanished we can get the 'n' value as 85
  Thus 85 is the correct answer
• 4 years agoHelpfull: Yes(0) No(0)