The amount of water (in ml) that should be added to reduce 9 ml lotion, containing 50% alcohol, to a lotion containing 30% alcohol, is:

• 50% of 9ml = 30% of x ml. so, x= 15ml. now, amount of water to be added= 15-9= 6ml, as alcohol remains same.
  
• 12 years agoHelpfull: Yes(35) No(5)
• alcohol = 9*50/100 = 4.5 ml
  30*x/100 = 4.5 ...... x = total amount of solution for which 4.5 ml forms 30% conc.
  x = 15ml
  
  thus water to be added = 15-9 = 6ml
  
• 12 years agoHelpfull: Yes(14) No(1)
• 50% of 9ml=30% of x ml
  as the amt of of alcohol will remian the same.
  hence the answer is 15ml
• 12 years agoHelpfull: Yes(9) No(14)
• let is assume that the lotion has 50% alcohol and 50% water.
  ratio = 1:1
  alcohol=water=4.5ml
  now if we want the quantity of alcohol- 30%
  the quantity of water = 70%
  the new ratio = 3:7
  let x ml of water be added
  we get : 4.5/4.5+x = 3/7
  or x=6
  hence 6ml of water is added. (ans)
• 8 years agoHelpfull: Yes(3) No(0)
• 50% of 9ml =30% of xml
  50/100*9=30/100*x
  x=15
  since it is reduced by 9ml we have,
  15ml-9ml=6ml
• 8 years agoHelpfull: Yes(3) No(0)