A container has 75% milk and 25% water. If I add 2 litres of water, then there will be equal amount of milk and water in the container. What is the amount of milk present in the container?

To solve this problem, we need to understand that before adding the water, the milk makes up 75% of the total liquid in the container.

Step 1: Let's assume the total amount of liquid in the container before adding water is 'x' litres.

Step 2: Since the milk makes up 75% of the total liquid, the amount of milk in the container is 0.75x litres.

Step 3: After adding 2 litres of water, the total amount of liquid in the container becomes (x + 2) litres.

Step 4: According to the problem, after adding 2 litres of water, the amount of milk and water in the container is equal. So, the amount of milk, which is 0.75x, is equal to half of the new total amount of liquid, which is (x + 2)/2.

Step 5: We can set up the equation 0.75x = (x + 2)/2 and solve for 'x'.

Step 6: Multiplying both sides of the equation by 2 to get rid of the denominator on the right side, we get 1.5x = x + 2.

Step 7: Subtract 'x' from both sides of the equation to isolate 'x' on one side, we get 0.5x = 2.

Step 8: Finally, divide both sides of the equation by 0.5 to solve for 'x', we get x = 4.

So, the total amount of liquid in the container before adding water is 4 litres.

Step 9: To find the amount of milk in the container, we multiply this by 75%, or 0.75. So, 0.75 * 4 = 3 litres.

Therefore, the amount of milk present in the container is 3 litres.