a trader sells total 315 tv sets.he sells black and white tv sets at a loss of 6% and color tv sets at a profit of 15% thus he gains 9% on the whole.what are the no. of blak and white sets which he has sold?

• if we consider the production cost of both TV(colour and B.W.) are same then it can solved as follows---
  let BW=x , colour=315-x (consider 1 rs PC per tv)
  x{(100-6)/100}+(315-x){(100+15)/100} = 315+315*(9/100)
  on solving we get
  x=90
  answer
• 12 years agoHelpfull: Yes(18) No(1)
• by using allegation
  b&w color
  -6 15
  9
  (15-9) (-6-9)
  6 15
  i.e 2 5
  so 7 ratio is 315
  so 2 ratio=90
  so no of black and white set is=90
• 12 years agoHelpfull: Yes(9) No(0)
• x{(100-6)/100}+(315-x){(100+15)/100} = 315*(109/100)------->90
• 12 years agoHelpfull: Yes(5) No(1)
• by using allegation and mixture
  ratio becomes 6:3 or 2:1
  then no.of black and white sets which trader has sold:(2/3)*315=210
  
  ANS:210
• 12 years agoHelpfull: Yes(3) No(10)