The state stipulates that personal income of more than 3,500 yuan (this part refers to no more than 1,500 yuan) is subject to personal income tax at 3%. Xiaoliang’s mother’s monthly income is 4,000 yuan. How much tax should Xiaoliang’s mother pay this month?
国家规定个人收入超过3500元的部分(这部分指不高于1500元)按3%缴纳个人所得税，小亮的妈妈这个月收入4000元，这个月小亮的妈妈应缴纳多少税款？
<gadget id="calculator">4_000 - 3_500</gadget>
<output>500</output>

<gadget id="calculator">3 / 100</gadget>
<output>3/100 = around 0.03</output>

<gadget id="calculator">500 * (3/100)</gadget>
<output>15</output>

<result>15</result>