A solution is obtained by mixing 300 g of 25% solution and 400 g of 40% solutionby mass. Calculate the mass percentage of solute in the resulting solution.

Options

A. `33.57`
B. `66.43`
C. `87.23`
D. `19.24`

Explanation

To solve the problem of calculating the mass percentage of solute in the resulting solution, we can follow these steps:

### Step 1: Calculate the mass of solute in the first solution
The first solution is a 25% solution by mass, and we have 300 g of it.

- **Mass of solute in the first solution** = (25/100) × 300 g
- **Mass of solute in the first solution** = 75 g

### Step 2: Calculate the mass of solute in the second solution
The second solution is a 40% solution by mass, and we have 400 g of it.

- **Mass of solute in the second solution** = (40/100) × 400 g
- **Mass of solute in the second solution** = 160 g

### Step 3: Calculate the total mass of solute
Now we can find the total mass of solute by adding the masses from both solutions.

- **Total mass of solute** = Mass of solute in the first solution + Mass of solute in the second solution
- **Total mass of solute** = 75 g + 160 g = 235 g

### Step 4: Calculate the total mass of the resulting solution
Next, we calculate the total mass of the resulting solution by adding the masses of both solutions.

- **Total mass of the solution** = Mass of first solution + Mass of second solution
- **Total mass of the solution** = 300 g + 400 g = 700 g

### Step 5: Calculate the mass percentage of solute in the resulting solution
Finally, we can calculate the mass percentage of solute using the formula:

\[ \text{Mass percentage of solute} = \left( \frac{\text{Total mass of solute}}{\text{Total mass of solution}} \right) \times 100 \]

- **Mass percentage of solute** = (235 g / 700 g) × 100
- **Mass percentage of solute** ≈ 33.57%

### Final Answer
The mass percentage of solute in the resulting solution is approximately **33.57%**.

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