Alligation or Mixture problems
Tea worth Rs. 126 per kg and Rs. 135 per kg are mixed with a third variety in the ratio 1 : 1 : 2. If mixture is worth Rs. 153 per kg, the price of the third variety per kg will be:
Here first two varieties of tea are mixed in equal ratio.So their average price = (126 + 135) /2 = Rs. 130.50 Let price of the third variety per kg be Rs. A; then now mixture is formed by two varieties one at Rs. 130.50 per kg and other at Rs. A per kg in the same ratio 2 : 2 i.e, 1 : 1 By the rule of alligation,(A - 153) / (22.50) = 1 ? A ? 153 = 22.50 ? A = Rs. 175.50
Let the capacity of the pot be 'P' litres.Quantity of milk in the mixture before adding milk = 4/9 (P - 8)After adding milk, quantity of milk in the mixture = 6/11 P.6P/11 - 8 = 4/9(P - 8)10P = 792 - 352 => P = 44. The capacity of the pot is 44 liters.
Average speed = (100 / 10) = 10 km/hr. Ratio of time taken at 7 km/hr to 12 km/hr = 2 : 3 Time taken at 7 km/hr = 2 (2 + 3) × 10 = 4 hrs. Distance covered at 7 km/hr = 7 × 4 = 28 km. Distance covered at 12 km/hr = 100 ? 28 = 72 km.
Ratio of milk and water = 2 : 1Quantity of milk = 60 X 2/3 = 40 litreQuantity of water = 20 litreTo make ratio, 1: 2, we have to double the water that of milkSo, water should be 80 litre.That means 80 ? 20 = 60 litre water to be added.