Alligation or Mixture problems
If a man buys 1 lt of milk for Rs.12 and mixes it with 20% water and sells it for Rs.15, then what is the percentage of gain?
Total quantity of iron = 4 (1 / 4) + 6 (2 / 3) = 1 + 4 = 5 kg. Total quantity of tin = (4 + 6) ? 5 = 5 kg. In the resultant mixture, iron : tin = 5 : 5 or 1 : 1
Number of liters of water in 150 liters of the mixture = 20% of 150 = 20/100 x 150 = 30 liters.P liters of water added to the mixture to make water 25% of the new mixture.Total amount of water becomes (30 + P) and total volume of mixture is (150 + P).(30 + P) = 25/100 x (150 + P)120 + 4P = 150 + P => P = 10 liters.
Let cost price of spirit be Re. 1 per liter. Then SP of mixture = Re. 1 per liter Gain = 25% So, CP of mixture = 1 × (100 / 125) = Re. 4 / 5We assume that CP of water is zero. Using allegation rule on cost price, Water should be mixed to spirit in the ratio (1 / 5) : (4 / 5) or 1 : 4
Let C.P. of 1 liter milk be Re. 1, Gain = 16 2/3 % = 50/3 %and S.P. of 1 liter mixture = Re. 1 then C.P. of 1 liter mixture = (1 x (100 x 3) / 350) = Re. (6 / 7) By the rule of alligation,Hence, required ratio = (1/ 7) : (6 / 7) = 1 : 6
EXAMIANS