Karan purchased one dozen pens for Rs. 120/-and sold a pack of 3 pens for Rs. 35/-each .What is his gain ?
A. `16.67%`
B. `20%`
C. `15%`
D. `33.33%`

Options

A. A
B. C
C. B
D. D

Answer

To find Karan's gain percentage from selling pens, we can follow these steps:

### Step 1: Determine the Cost Price (CP)
Karan purchased 1 dozen pens for Rs. 120. Since 1 dozen equals 12 pens, we can say:
- Cost Price (CP) of 12 pens = Rs. 120

### Step 2: Calculate the Selling Price (SP) of 3 Pens
Karan sells a pack of 3 pens for Rs. 35. Therefore:
- Selling Price (SP) of 3 pens = Rs. 35

### Step 3: Calculate the Selling Price of 12 Pens
To find out the selling price of all 12 pens, we can calculate how many packs of 3 pens are in 12 pens:
- Number of packs in 12 pens = 12 pens / 3 pens per pack = 4 packs
- Selling Price (SP) of 12 pens = 4 packs × Rs. 35 per pack = Rs. 140

### Step 4: Calculate the Gain
Gain can be calculated by subtracting the cost price from the selling price:
- Gain = Selling Price - Cost Price
- Gain = Rs. 140 - Rs. 120 = Rs. 20

### Step 5: Calculate the Gain Percentage
Gain percentage can be calculated using the formula:
\[ \text{Gain Percentage} = \left( \frac{\text{Gain}}{\text{Cost Price}} \right) \times 100 \]
Substituting the values we have:
- Gain Percentage = \( \left( \frac{20}{120} \right) \times 100 \)

### Step 6: Simplify the Gain Percentage Calculation
- Gain Percentage = \( \frac{20}{120} \times 100 = \frac{1}{6} \times 100 \)
- Gain Percentage = 16.67%

### Conclusion
The gain percentage is 16.67%. Therefore, the correct answer is:
**A. 16.67%**

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