If it is stipulated that the part of the employee's monthly salary exceeding 800 yuan should be paid personal income tax at a rate of 5%, and Xiaojun's father's monthly salary is 1,200 yuan, how much personal income tax should he pay?
如果规定职工每月工资超过800元的部分按5%的税率缴纳个人所得税，小军爸爸这个月工资是1200元，那么他应缴纳个人所得税多少元？
<gadget id="calculator">1_200 - 800</gadget>
<output>400</output>

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

<gadget id="calculator">400 * (1/20)</gadget>
<output>20</output>

<result>20</result>