A fruit seller purchased 20 kg of grapes for Rs. 400. If he sells the graphs at a rate of Rs. 50 per kg, then find his profit percentage.

Explanation

To find the profit percentage for the fruit seller who purchased grapes, we can follow these steps:

### Step 1: Determine the Cost Price (CP)
The fruit seller purchased 20 kg of grapes for Rs. 400.

- **Cost Price (CP)** = Total Cost / Total Weight
- CP = Rs. 400 / 20 kg = Rs. 20 per kg

### Step 2: Determine the Selling Price (SP)
The selling price of grapes is given as Rs. 50 per kg.

- **Selling Price (SP)** = Rs. 50 per kg

### Step 3: Calculate the Profit
Profit can be calculated using the formula:

- **Profit** = Selling Price - Cost Price
- Profit = Rs. 50 - Rs. 20 = Rs. 30 per kg

### Step 4: Calculate the Profit Percentage
Profit percentage is calculated using the formula:

- **Profit Percentage** = (Profit / Cost Price) × 100
- Profit Percentage = (Rs. 30 / Rs. 20) × 100

Now, simplifying this:

- Profit Percentage = 1.5 × 100 = 150%

### Final Answer
The profit percentage of the fruit seller is **150%**.

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