The naughty father deposited 10,000 yuan in the bank for three years, with an annual interest rate of 2.70%. If you have to pay 20% interest income tax when it is due, how much is the bank's total principal and interest payable to naughty dad?
淘气的爸爸在银行存了10000元人民币，定期三年，年利率是2.70%．到期时如果要交纳利息所得税20%，那么银行应付给淘气的爸爸本金和利息一共多少元？
<gadget id="calculator">2.7 / 100</gadget>
<output>0.027</output>

<gadget id="calculator">10_000 * 0.027 * 3</gadget>
<output>810</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">810 * (4/5)</gadget>
<output>648</output>

<gadget id="calculator">10_000 + 648</gadget>
<output>10_648</output>

<result>10_648</result>