Lele did 240 cross-point calculation questions, and the correct rate was 85%. How many questions did he do wrong?
乐乐做了240道口算题，正确率为85%，他做错了多少道题．
<gadget id="calculator">85 / 100</gadget>
<output>17/20 = around 0.85</output>

<gadget id="calculator">240 * (17/20)</gadget>
<output>204</output>

<gadget id="calculator">240 - 204</gadget>
<output>36</output>

<result>36</result>