There are total 24 hats of blue and red colour. The average cost of blue colour hats is Rs. 65. The average cost of red colour hats is Rs. 35. The average cost of all the hats is Rs. 50. What is the number of red colour hats?

Two alloys of gold and copper are mixed in the ratio 2:3. The first alloy has gold and copper in the ratio 4:1, and the second in the ratio 1:4. What is the ratio of gold to copper in the resulting mixture?

There are total 24 hats of blue and red colour. The average cost of blue colour hats is Rs. 65. The average cost of red colour hats is Rs. 35. The average cost of all the hats is Rs. 50. What is the number of red colour hats?

How much water must be added to 60 litres of milk at 1$$\frac12$$​ litres for Rs. 20 so as to have a mixture worth Rs. 10$$\frac23$$​ a litre?

The ratio of milk and water in a 30 litre mixture is 3 : 2. Find the quantity of water to beadded to the mixture in order to make this ratio 1:1.

In what ratio should sugar costing ₹10 per kg be mixed with sugar costing ₹61 per kg sothat by selling the mixture at ₹31.5 per kg, there is a profit of 26%?

In what ratio should sugar costing ₹74 per kg be mixed with sugar costing ₹41 per kg sothat by selling the mixture at ₹85.8 per kg, there is a profit of 30%?

In what ratio should sugar costing ₹64 per kg be mixed with sugar costing ₹22 per kg so that by selling the mixture at ₹70.8 per kg, there is a profit of 20%?