A batch of parts is processed, and 4 parts are found to be unqualified after inspection. The pass rate is 98%. How many parts are qualified?
加工一批零件，经检验发现有4个不合格，合格率是98%，有多少个零件合格．
<gadget id="calculator">98 / 100</gadget>
<output>49/50 = around 0.98</output>

<gadget id="calculator">1 - (49/50)</gadget>
<output>1/50 = around 0.02</output>

<gadget id="calculator">4 / (1/50)</gadget>
<output>200</output>

<gadget id="calculator">200 - 4</gadget>
<output>196</output>

<result>196</result>