Answer:
200 mL shampoo - 1050 ml water
500 mL shampoo - 2625 mL water
Explanation:
1) 400 ml shampoo , should be mixed 2500 - 400 = 2100 mL of water.
2) 400 mL shampoo - 2100 mL water
200 mL shampoo - x mL water
x = 200*2100/400 = 1050 mL water
3) 400 mL shampoo - 2100 mL water
500 mL shampoo - x mL water
x = 500*2100/400 = 2625 mL water