Grandma Zhang saved 2,000 yuan in postal savings for three years. If the annual interest rate is 5.40% (deducting 5% interest tax), how much is the interest after tax when it expires.
张奶奶在邮政储蓄存了2000元，定期三年，如果按年利率5.40%计算(扣除5%的利息税)，到期时除去税后利息是多少元．
<gadget id="calculator">5.4 / 100</gadget>
<output>0.054</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">2_000 * 0.054 * 3 * (19/20)</gadget>
<output>307.8</output>

<result>307.8</result>