Calculate the Average Actual Profit.

The profits and losses for the previous years are:
2017 Profit: ₹ 5,000
2018 Loss: ₹ 8,500
2019 Profit: ₹ 25,000
2020 Profit: ₹ 37,500

$$\text{Total Profit} = 5,000 - 8,500 + 25,000 + 37,500 = 59,000$$ $$\text{Average Actual Profit} = \frac{59,000}{4} = 14,750$$

The remuneration from alternative employment of the proprietor is ₹ 3,000 p.a. This is a normal expense and should be deducted from the average actual profit.

$$\text{Adjusted Average Actual Profit} = 14,750 - 3,000 = 11,750$$

The average Capital Employed is ₹ 1,00,000. The normal rate of return is not explicitly stated in the question. We will assume a Normal Rate of Return of 10%, which is common in such problems.

$$\text{Normal Profit} = \text{Average Capital Employed} \times \text{Normal Rate of Return}$$ $$\text{Normal Profit} = 1,00,000 \times \frac{10}{100} = 10,000$$

Super Profit is the excess of Adjusted Average Actual Profit over Normal Profit.

$$\text{Super Profit} = \text{Adjusted Average Actual Profit} - \text{Normal Profit}$$ $$\text{Super Profit} = 11,750 - 10,000 = 1,750$$

Goodwill is to be calculated on the basis of 3 years' purchases of Super Profits.

$$\text{Goodwill} = \text{Super Profit} \times \text{Number of years' purchases}$$ $$\text{Goodwill} = 1,750 \times 3 = 5,250$$

The value of goodwill is $\text{₹ 5,250}$.