A shopkeeper sells his goods at C.P. but uses 900gm weight find profit %

Answer

To solve the problem step by step, we need to find the profit percentage when a shopkeeper sells goods at the cost price (C.P.) but uses a weight of 900 grams instead of 1000 grams.

### Step-by-Step Solution:

1. **Understanding the Situation**:
- The shopkeeper is selling goods at the cost price (C.P.), which means he sells 1 kg (1000 grams) of goods at the price he paid for it.
- However, he is using a weight of 900 grams instead of 1000 grams.

2. **Calculating the Effective Profit**:
- When he sells 900 grams, he is effectively giving less product than what the customer thinks they are buying (which is 1000 grams).
- The difference in weight is:
\[ 1000 \text{ grams} - 900 \text{ grams} = 100 \text{ grams} \]
- This means he is making a profit of 100 grams worth of goods.

3. **Calculating the Profit Percentage**:
- To find the profit percentage, we use the formula:
\[ \text{Profit Percentage} = \left( \frac{\text{Profit}}{\text{Cost Price}} \right) \times 100 \]
- Here, the profit is 100 grams, and the cost price for 900 grams is 900 grams (since he sells it at C.P.).
- Plugging in the values:
\[ \text{Profit Percentage} = \left( \frac{100 \text{ grams}}{900 \text{ grams}} \right) \times 100 \]

4. **Simplifying the Calculation**:
- Simplifying the fraction:
\[ \text{Profit Percentage} = \left( \frac{100}{900} \right) \times 100 = \frac{10000}{900} = \frac{1000}{90} = \frac{100}{9} \approx 11.11\% \]

5. **Final Result**:
- Therefore, the profit percentage when the shopkeeper uses a 900-gram weight instead of a 1 kg weight is:
\[ \text{Profit Percentage} \approx 11.11\% \text{ or } \frac{11}{9}\% \]