An ally of tin and copper consists of 24 parts of tin and 136 parts of copper. Find the percentage of copper in the alloy.

Answer

To find the percentage of copper in the alloy, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the parts of tin and copper**:
- The alloy consists of 24 parts of tin and 136 parts of copper.
- Let’s denote the parts of tin as \( T = 24 \) and the parts of copper as \( C = 136 \).

2. **Calculate the total parts of the alloy**:
- The total parts of the alloy is the sum of the parts of tin and copper.
\[ \text{Total parts} = T + C = 24 + 136 = 160 \]

3. **Calculate the percentage of copper**:
- The formula to find the percentage of copper in the alloy is:
\[ \text{Percentage of copper} = \left( \frac{C}{\text{Total parts}} \right) \times 100 \]
- Substituting the values we have:
\[ \text{Percentage of copper} = \left( \frac{136}{160} \right) \times 100 \]

4. **Simplify the fraction**:
- To simplify \( \frac{136}{160} \), we can divide both the numerator and the denominator by 16:
\[ \frac{136 \div 16}{160 \div 16} = \frac{8.5}{10} = \frac{85}{100} \]

5. **Calculate the final percentage**:
- Now we can calculate:
\[ \text{Percentage of copper} = \frac{85}{100} \times 100 = 85\% \]

### Final Answer:
The percentage of copper in the alloy is **85%**.

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