Alligation or Mixture problems
A dishonest milkman professes to sell his milk at C. P. But he mixes it with water and thereby gains 25 %. The % of water in the mixture is ?
Cost price of the mixture = 15 × (100 / 180) = Rs. 25/3 per kg
(Quantity of rice @ Rs. 8 per kg) / (Quantity of rice @ Rs.10 per kg) = (5 / 3) / (1/3) = 1/5
Quantity of rice @ Rs. 10 per kg = 25 × (1/ 5) = 5 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.
Let the price per kg of mixed variety be Rs. P; then By the rule of alligation,Now, (20 - P) / (P - 15) = (2 / 3) ? 60 ? 3P = 2P ? 30 ? 5P = 90 ? P = Rs. 18
Milk Water 74% 26% (initially) 76% 24% ( after replacement) Left amount = Initial amount 1 - r e p l a c e d a m o u n t t o t a l a m o u n t 24 = 26 1 - 7 k => k = 91