A milk man makes a profit of 20% on the sale of milk. If he were to add 10% water to the milk, by what % would his profit increase?  Pick:
A) 30
B) 40⁄3
C) 22
D) 10
E) None of these
Let profit per litre = 20   So, C.P. /litre = 100   S.P. / litre = 120   On adding 10% water to the milk   C.P. / 9⁄10 litre = 100   S.P. / 9⁄10 litre = 120   S.P / litre = 120×10/9=400/3   ⇒ Profit / litre = 400⁄3 - 100 = 33.33   % by which profit increases = 33.33 – 20 = 13.3   Answer 40⁄3
<result>B</result>
A milk man makes a profit of 20% on the sale of milk. If he were to add 10% water to the milk, by what % would his profit increase?