Explanation:

- The cost price (CP) of the chair is Rs 3750.

- The person originally sold the chair at a profit of 13%.

- So, the selling price (SP) at 13% profit is given by:

SP = CP + 13% of CP

SP = Rs 3750 + (13/100) * Rs 3750

SP = Rs 3750 + Rs 487.50

SP = Rs 4237.50

- If sold for Rs 607.50 more, the new SP would be:

New SP = Rs 4237.50 + Rs 607.50

New SP = Rs 4845

- New profit percentage (x%), (New SP - CP)/CP * 100 = x

x = [(Rs 4845 - Rs 3750) / Rs 3750] * 100

x = (Rs 1095 / Rs 3750) * 100

x = 29.2%

- Option 4 - 29.2 is correct.