The annual interest rate of the three-year national construction bond is 2.4%. Teacher Wang bought 20,000 yuan. How much will he get back with the principal and interest when it expires? (National bonds do not pay interest tax)
三年期国家建设债券的年利率是2.4%，王老师购买20000元，到期时连本带利一共取回多少钱？(国债不交利息税)
<gadget id="calculator">2.4 / 100</gadget>
<output>0.024</output>

<gadget id="calculator">20_000 * 0.024 * 3</gadget>
<output>1_440</output>

<gadget id="calculator">20_000 + 1_440</gadget>
<output>21_440</output>

<result>21_440</result>