Alligation or Mixture problems
If 4 kg of an alloy made of 1/4th iron and rest is mixed with 6 kg of another alloy made of 2/3rd iron and rest tin, find the ratio of iron to tin in the resultant mixture.
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
According to figure we can find that the ration would be 1 : 7.Quantity sold at 10% profit = 1 / (1 + 7)× 160 = 20 kgs. Quantity sold at 6% loss = (160 ? 20) = 140 kgs.
Let the price of the mixed variety be Rs. x per kg. By the rule of alligation, we have : Cost of 1 kg of type 1 rice Cost of 1 kg of type 2 rice ? (20-x)/(x-15) = 2/3 ? 60 - 3x = 2x - 30 ? x = 18.