If the selling price of 10 articles is equal to the cost price of 11 articles, then the gain percent is

Options

A. 10
B. 11
C. 15
D. 25

Answer

To solve the problem, we need to find the gain percentage when the selling price of 10 articles is equal to the cost price of 11 articles.

### Step-by-Step Solution:

1. **Define Variables**:
Let the cost price (CP) of one article be \( x \).

2. **Calculate Cost Price of 10 Articles**:
The cost price of 10 articles would be:
\[ \text{CP of 10 articles} = 10 \times x = 10x \]

3. **Calculate Cost Price of 11 Articles**:
The cost price of 11 articles would be:
\[ \text{CP of 11 articles} = 11 \times x = 11x \]

4. **Set Up the Equation**:
According to the problem, the selling price (SP) of 10 articles is equal to the cost price of 11 articles:
\[ \text{SP of 10 articles} = \text{CP of 11 articles} \]
Therefore:
\[ \text{SP of 10 articles} = 11x \]

5. **Calculate Selling Price of One Article**:
The selling price of one article can be calculated as:
\[ \text{SP of 1 article} = \frac{11x}{10} \]

6. **Calculate Gain**:
The gain from selling one article is:
\[ \text{Gain} = \text{SP} - \text{CP} = \frac{11x}{10} - x \]
Simplifying this gives:
\[ \text{Gain} = \frac{11x}{10} - \frac{10x}{10} = \frac{x}{10} \]

7. **Calculate Gain Percentage**:
The gain percentage is calculated using the formula:
\[ \text{Gain Percentage} = \left( \frac{\text{Gain}}{\text{CP}} \right) \times 100 \]
Substituting the values we have:
\[ \text{Gain Percentage} = \left( \frac{\frac{x}{10}}{x} \right) \times 100 = \frac{1}{10} \times 100 = 10\% \]

### Final Answer:
The gain percentage is **10%**.