A developer sells houses in the form of installment payment. Xiaoming’s family bought a new house with a current price of 480,000 yuan. When buying a house, a down payment (first year) of 280,000 yuan is required. From the second year onwards, the house payment payable each year is The sum of 20,000 yuan and the interest on the remaining arrears from the previous year, the annual interest rate on the remaining arrears is known to be 4%, how much interest will be paid in total after the purchase price is fully paid off?
某开发商按照分期付款的形式售房，小明家购买了一套现价48万的新房，购房时需首付(第一年)房款28万元，从第二年起，以后每年应付房款为20000元与上一年剩余欠款的利息之和，已知剩余欠款的年利率为4%，问当全部付清购房款后，共付利息多少元？
<gadget id="calculator">110 * 0.04</gadget>
<output>4.4</output>

<gadget id="calculator">4.4 * 10_000</gadget>
<output>44_000</output>

<result>44_000</result>