MalachiKeti
10% of milk and water solution with 40% milk is replaced with water. What is concentration of milk in the resultant solution?
A. 20%
B. 32%
C. 18%
D. 40%
E. 36%
We need to calculate the
concentration of milk in the solution after
10% of it is replaced with water when the initial solution contains
40% milk. Here's a step-by-step explanation:
Step 1: Understand the problem.
- Initial concentration of milk: 40%.
- Replacement process: 10% of the solution is replaced with water.
- This process reduces the milk concentration since pure water (0% milk) is added.
Step 2: Define the key formula.
Each time we replace a fraction of the solution with water, the new concentration of milk can be calculated using the formula:
Cnew=Cold×(1−r)
Where:
- Cnew = new concentration of milk.
- Cold = old concentration of milk.
- r = fraction of solution replaced with water (10% = 0.1).
Step 3: Perform the calculations.
- First replacement:
Cnew=40%×(1−0.1)=40%×0.9=36%
Thus, after the replacement, the concentration of milk in the resultant solution is
36%.
Final Answer:
The concentration of milk in the resultant solution is
36%, which corresponds to
Option E.