Calculate the percentage composition of a solution obtained by mixing 200 g of a `20%` and 300 g of a `30%` solution by weight.

Answer

To calculate the percentage composition of the solution obtained by mixing 200 g of a 20% solution and 300 g of a 30% solution, we will follow these steps:

### Step 1: Calculate the weight of solute in the first solution
The first solution is 20% by weight, and we have 200 g of it.

\[ \text{Weight of solute in the first solution} = \frac{20}{100} \times 200 = 40 \text{ g} \]

### Step 2: Calculate the weight of solute in the second solution
The second solution is 30% by weight, and we have 300 g of it.

\[ \text{Weight of solute in the second solution} = \frac{30}{100} \times 300 = 90 \text{ g} \]

### Step 3: Calculate the total weight of solute after mixing
Now, we can find the total weight of solute from both solutions.

\[ \text{Total weight of solute} = 40 \text{ g} + 90 \text{ g} = 130 \text{ g} \]

### Step 4: Calculate the total weight of the mixed solution
Next, we need to find the total weight of the mixed solution.

\[ \text{Total weight of the solution} = 200 \text{ g} + 300 \text{ g} = 500 \text{ g} \]

### Step 5: Calculate the percentage composition of the mixed solution
Finally, we can calculate the percentage composition of the solute in the mixed solution.

\[ \text{Percentage composition} = \left( \frac{\text{Total weight of solute}}{\text{Total weight of solution}} \right) \times 100 = \left( \frac{130 \text{ g}}{500 \text{ g}} \right) \times 100 = 26.0\% \]

### Final Answer
The percentage composition of the mixed solution is **26.0%**.

---