The difference between the selling prices of an article at profits 5% and 10% is Rs 30. What will be the cost price of the article ?
A)Rs 600
B)Rs 1200
C)Rs 500
D)Rs 900

Options

A. Rs 600
B. Rs 1200
C. Rs 500
D. Rs 900

Answer

To solve the problem, we need to find the cost price of an article given that the difference between its selling prices at 5% and 10% profit is Rs 30.

### Step-by-Step Solution:

1. **Understand the Selling Prices**:
- Let the cost price (CP) of the article be \( x \).
- Selling price at 5% profit = \( x + 0.05x = 1.05x \)
- Selling price at 10% profit = \( x + 0.10x = 1.10x \)

2. **Set Up the Equation**:
- According to the problem, the difference between the selling prices at 10% and 5% profit is Rs 30:
\[ 1.10x - 1.05x = 30 \]

3. **Simplify the Equation**:
- Combine like terms:
\[ 0.05x = 30 \]

4. **Solve for Cost Price (CP)**:
- To find \( x \), divide both sides by 0.05:
\[ x = \frac{30}{0.05} = 600 \]

5. **Conclusion**:
- The cost price of the article is Rs 600.

### Final Answer:
The cost price of the article is **Rs 600** (Option A).

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