Explanation:

- Let's understand the situation: The dealer offers a 10% discount on the marked price yet still manages to make a 5% profit based on the cost price of Rs300.

- To achieve a 5% profit, the selling price of the article must be Rs300 + 5% of Rs300 = Rs315.

- The selling price after a 10% discount would be 90% of the marked price.

- Therefore, 0.9 (Marked Price) = Rs315.

- Solving for the marked price: Marked Price = Rs315 / 0.9 = Rs350.

- Option 4: Rs350 is the right marked price.

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