Xiaoxiao deposited RMB 20,000 in the bank for three years, with an annual interest rate of 2.70%. How much is the principal and interest payable by the bank to Xiaoxiao?
笑笑在银行存了20000元人民币，定期三年，年利率是2.70%．银行应付给笑笑本金和利息一共多少元？
<gadget id="calculator">2.7 / 100</gadget>
<output>0.027</output>

<gadget id="calculator">20_000 * 0.027 * 3</gadget>
<output>1_620</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">1_620 * (19/20)</gadget>
<output>1_539</output>

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

<result>21_539</result>