Now the annual interest rate of the 3-year fixed deposit is 3.33%, and 20% interest tax will be paid when it matures. Dad deposits 4000 yuan for 3 years fixed deposit, how much interest will he actually get when it matures?
现在3年定期的存款年利率是3.33%，到期还要缴20%的利息税，爸爸存4000元3年定期，到期实得多少元利息．
<gadget id="calculator">3.33 / 100</gadget>
<output>0.0333</output>

<gadget id="calculator">4_000 * 3 * 0.0333</gadget>
<output>399.6</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">399.6 * (4/5)</gadget>
<output>319.68</output>

<result>319.68</result>