For calculating the percentage of discount, we can use the formula:
Percentage of discount = (Discount amount / Original price) * 100
We have given that the discounted price is Birr 51,000 and the discount amount is Birr 9,000,we need to find the original price.
Original price = Discounted price + Discount amount
Original price = 51,000 + 9,000 = 60,000 Birr
Now, we can calculate the percentage of discount:
Percentage of discount = (9,000 / 60,000) * 100 = 15%
Hence, the percentage of discount for the four-door model is 15%.