1. **State the problem:** A house is sold for 3000000 FRW, and the bank requires a 20% down payment. We need to find the amount of the mortgage. 2. **Formula and explanation:** The mortgage amount is the remaining price after the down payment. The down payment is 20% of the total price. 3. **Calculate the down payment:** $$\text{Down payment} = 20\% \times 3000000 = 0.20 \times 3000000 = 600000$$ 4. **Calculate the mortgage amount:** $$\text{Mortgage} = \text{Total price} - \text{Down payment} = 3000000 - 600000 = 2400000$$ 5. **Answer:** The amount of the mortgage is 2400000 FRW.