A sold his pen at a profit of ₹13. He calculated the profit percentage on selling price and found it to be 20%. The cost price (in ₹) of the pen is:

Options

A. 39
B. 65
C. 52
D. 13

Answer

To find the cost price of the pen sold by A, we can follow these steps:

### Step 1: Understand the given information
- Profit made by A = ₹13
- Profit percentage on selling price = 20%

### Step 2: Set up the profit percentage formula
The profit percentage is given by the formula:
\[ \text{Profit Percentage} = \left( \frac{\text{Profit}}{\text{Selling Price}} \right) \times 100 \]
Since the profit percentage is 20%, we can express this as:
\[ 20 = \left( \frac{13}{\text{Selling Price}} \right) \times 100 \]

### Step 3: Rearrange the formula to find Selling Price (SP)
Rearranging the above equation gives:
\[ \text{Selling Price} = \frac{13 \times 100}{20} \]
Calculating this:
\[ \text{Selling Price} = \frac{1300}{20} = 65 \]
So, the Selling Price (SP) of the pen is ₹65.

### Step 4: Calculate the Cost Price (CP)
We know that:
\[ \text{Profit} = \text{Selling Price} - \text{Cost Price} \]
Substituting the known values:
\[ 13 = 65 - \text{Cost Price} \]
Rearranging gives:
\[ \text{Cost Price} = 65 - 13 = 52 \]

### Conclusion
The cost price of the pen is ₹52.