Alligation or Mixture problems
A mixture of 20 kg of spirit and water contains 10 % water. How much water must be added to this mixture to raise the percentage of water to 25 %?
Let the amount of juice and water in original mixture '4x' litre and '3x' litre respectively. According to given data, 4x/3x+6 =8/7 28x=24x+48 28x?24x=48 4x = 48 x = 12 Amount of juice = 4x = 4×12 = 48 litre.
According to question , Total C. P. of 200 kg of mixture = Rs. (80 × 6·75 + 120 × 8)Total C. P. of 200 kg of mixture = Rs. 1500Average rate = Rs. 7·50 per kgRequired rate = 120% of Rs. 7·50Required rate = Rs. 9 per kg.