The selling price of an article is `6/5` of the cost price. The gain per cent is

Options

A. 0.2
B. 0.25
C. 0.3
D. 1.2

Answer

To solve the problem step by step, we will determine the gain percentage based on the given information about the selling price and cost price.

### Step-by-Step Solution:

1. **Let the Cost Price (CP) be x**:
- We denote the cost price of the article as \( x \).

**Hint**: Start by defining the cost price as a variable to simplify calculations.

2. **Determine the Selling Price (SP)**:
- According to the problem, the selling price is \( \frac{6}{5} \) of the cost price. Therefore, we can express the selling price as:
\[ SP = \frac{6}{5} \times x = \frac{6x}{5} \]

**Hint**: Use the relationship given in the problem to express the selling price in terms of the cost price.

3. **Calculate the Gain**:
- Gain is calculated as the difference between the selling price and the cost price:
\[ \text{Gain} = SP - CP = \frac{6x}{5} - x \]
- To perform the subtraction, we need a common denominator:
\[ \text{Gain} = \frac{6x}{5} - \frac{5x}{5} = \frac{6x - 5x}{5} = \frac{x}{5} \]

**Hint**: Remember to find a common denominator when subtracting fractions.

4. **Calculate the Gain Percentage**:
- The gain percentage is calculated using the formula:
\[ \text{Gain Percentage} = \left(\frac{\text{Gain}}{CP}\right) \times 100 \]
- Substituting the values we have:
\[ \text{Gain Percentage} = \left(\frac{\frac{x}{5}}{x}\right) \times 100 \]
- Simplifying this gives:
\[ \text{Gain Percentage} = \left(\frac{1}{5}\right) \times 100 = 20\% \]

**Hint**: When calculating percentages, ensure that you multiply by 100 after finding the ratio.

### Final Answer:
The gain percentage is **20%**.