Bhanu bought a fountain pen for Rs 12. Fow how much should she sell to gain 15%?

Answer

To find out how much Bhanu should sell the fountain pen for to gain a 15% profit, we can follow these steps:

### Step 1: Identify the Cost Price (CP)
The cost price of the fountain pen is given as Rs. 12.

### Step 2: Determine the Gain Percentage
The gain percentage is given as 15%.

### Step 3: Use the Formula for Selling Price (SP)
The formula to calculate the selling price when the gain percentage is known is:
\[ SP = CP \times \left( \frac{100 + \text{Gain Percentage}}{100} \right) \]

### Step 4: Substitute the Values into the Formula
Substituting the known values into the formula:
\[ SP = 12 \times \left( \frac{100 + 15}{100} \right) \]
This simplifies to:
\[ SP = 12 \times \left( \frac{115}{100} \right) \]

### Step 5: Calculate the Selling Price
Now, calculate the selling price:
\[ SP = 12 \times 1.15 = 13.8 \]

### Final Answer
Thus, Bhanu should sell the fountain pen for **Rs. 13.8** to gain a 15% profit.

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