Explanation:

- Let's denote the cost price of the article as 'C'.

- The profit when selling at Rs 5,600 is equal to the loss when selling at Rs 2,400.

- Profit = Selling Price - Cost Price = Rs 5,600 - C

- Loss = Cost Price - Selling Price = C - Rs 2,400

- Given, Profit = Loss, thus, Rs 5,600 - C = C - Rs 2,400

- Solving the equation:

$$

2C = 5,600 + 2,400

$$

$$

2C = 8,000 \Rightarrow C = 4,000

$$

- The profit percentage would be:

$$

\left(\frac{5,600 - 4,000}{4,000}\right) \times 100 = 40\%

$$

- Your chosen answer, Option 4: 40%, is correct .

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