Mom deposits 1,000 yuan in the bank and withdraws it in lump sum for three years. The annual interest rate is 2.70%. When the withdrawal is due, 20% interest tax is required. After tax payment, how much interest can my mother get back?
妈妈把1000元钱存入银行，整存整取三年，年利率是2.70%，到期取款时，需缴纳20%的利息税．纳税后，妈妈可以取回利息多少元．
<gadget id="calculator">2.7 / 100</gadget>
<output>0.027</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">1_000 * 0.027 * 3 * (4/5)</gadget>
<output>64.8</output>

<result>64.8</result>