It is the duty of every citizen to pay taxes according to law. Mr. Zhang’s total salary last month was 1,840 yuan. According to the relevant provisions of the Individual Income Tax Law, Mr. Zhang’s salary exceeding 1,600 yuan is subject to 5% personal income tax. So how much personal income tax should Mr. Zhang pay last month?
依法纳税是每个公民的义务．张老师上个月的工资总额为1840元，按照个人所得税法的有关规定，张老师的工资超过1600元的部分要缴纳5%的个人所得税，那么张老师上个月应缴纳个人所得税多少元？
<gadget id="calculator">1_840 - 1_600</gadget>
<output>240</output>

<gadget id="calculator">5 / 100</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">240 * (1/20)</gadget>
<output>12</output>

<result>12</result>