The mother deposits 2,000 yuan in the bank for her daughter's tuition fees for two years. If the annual interest rate is 2.25%, how much will be the after-tax interest when it matures?
妈妈为女儿存入银行2000元做学费，定期二年，如果年利率按2.25%，到期时应得税后利息多少元．
<gadget id="calculator">2.25 / 100</gadget>
<output>0.0225</output>

<gadget id="calculator">2_000 * 0.0225 * 2</gadget>
<output>90</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">90 * (4/5)</gadget>
<output>72</output>

<result>72</result>