Wang Gang deposits RMB 20,000 in the bank for 3 years with an annual interest rate of 2.7%. How much is the total amount of principal and after-tax interest that Wang Gang should get when it is due? (Interest tax rate is 5%)
王钢把20000元人民币存入银行，定期3年，年利率是2.7%．到期时，王钢应得本金和税后利息利息一共多少元？(利息税率为5%)
<gadget id="calculator">2.7 / 100</gadget>
<output>0.027</output>

<gadget id="calculator">5 / 100</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 - (1/20)</gadget>
<output>19/20 = around 0.95</output>

<gadget id="calculator">20_000 * 0.027 * 3 * (19/20)</gadget>
<output>1_539</output>

<gadget id="calculator">20_000 + 1_539</gadget>
<output>21_539</output>

<result>21_539</result>