Explanation:

- Let's assume the original bill amount is Rs. x.

- A single discount of 40% means you pay 60% of the bill, so the payment is \( 0.6 \times x \).

- Two successive discounts of 30% each mean you first pay 70% of the bill, then 70% of the remaining. The calculation becomes \( 0.7 \times 0.7 \times x = 0.49 \times x \).

- The difference between these two payment methods equals Rs. 220.

- Therefore, the equation is \( 0.6x - 0.49x = 220 \), leading to \( 0.11x = 220 \).

- Solving for x gives the original bill amount as Rs. 2000.

- Correct Answer: Option 4 - 2000