Mr. Zhang’s monthly salary is 2,000 yuan. The Personal Income Tax Law stipulates that when the monthly salary exceeds 1,200 yuan, the excess part shall be paid at the rate of (1/20) personal income tax. How much personal income tax does Mr. Zhang have to pay every month?
张老师每月工资2000元，个人所得税法规定每月工资超1200元时，超出部分按(1/20)的税率缴纳个人所得税，张老师每月要缴纳个人所得税多少元？
<gadget id="calculator">2_000 - 1_200</gadget>
<output>800</output>

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

<gadget id="calculator">800 * (1/20)</gadget>
<output>40</output>

<result>40</result>