Fangfang’s family recently bought a new house and borrowed 180,000 yuan from the bank with their personal provident fund. The loan period is 10 years. (Personal provident fund loan project: the annual interest rate is 4.00% for less than five years (including five years); the annual interest rate for more than five years is 4.50%)
芳芳家最近买了一套新房，用个人公积金向银行贷款18万元，贷款期限10年，到期共要还利息多少元？(个人公积金贷款项目：年利率%五年以下4.00%(含五年)；五年以上年利率4.50%)
<gadget id="calculator">18 * 10_000</gadget>
<output>180_000</output>

<gadget id="calculator">4.5 / 100</gadget>
<output>0.045</output>

<gadget id="calculator">180_000 * 0.045 * 10</gadget>
<output>81_000</output>

<result>81_000</result>