my country's personal income tax law stipulates that the part of the personal monthly income (excluding pension insurance, medical insurance, and unemployment insurance) exceeding 2,000 yuan shall be taxed at a certain rate, and the part exceeding 500 yuan (including 500 yuan) shall be taxed at a certain rate. 5% is paid, and the excess of 500 to 2,000 yuan is paid at 10%. If Dad's monthly salary is fixed at 4,200 yuan, including 300 yuan for three gold, how much personal income tax should dad pay every month?
我国个人所得税法规定：个人月收入(除去养老保险金、医疗保险金、失业保险金)中超过2000元的部分要按一定税率缴税，超过部分在500元以内(含500元)的部分按5%缴纳，超过部分在500～2000元的部分按10%缴纳，如果爸爸每月的工资定额为4200元，其中包括三金300元，爸爸每月应缴纳个人所得税多少元？
<gadget id="calculator">5 / 100</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">500 * (1/20)</gadget>
<output>25</output>

<gadget id="calculator">10 / 100</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1_400 * (1/10)</gadget>
<output>140</output>

<gadget id="calculator">25 + 140</gadget>
<output>165</output>

<result>165</result>