The new "Individual Income Tax Law" stipulates that the part of personal monthly salary income exceeding 3,500 yuan should be taxed at 3%. Uncle Zhang's monthly salary is 4,200 yuan. How much is his monthly income after paying personal income tax?
新《个人所得税法》规定，个人月工资收入超出3500元的部分应按3%纳税，张叔叔月工资4200元，他每月缴纳个人所得税后的收入是多少元？
<gadget id="calculator">4_200 - 3_500</gadget>
<output>700</output>

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

<gadget id="calculator">700 * (3/100)</gadget>
<output>21</output>

<gadget id="calculator">4_200 - 21</gadget>
<output>4_179</output>

<result>4_179</result>