15.104/((548+396)*(□-7.52))=0.02 (only fill in □, do not write the process)
15.104/((548+396)*(□-7.52))=0.02(只填□，不写过程)
<gadget id="calculator">548 + 396</gadget>
<output>944</output>

<gadget id="calculator">15.104 / 0.02 / 944</gadget>
<output>0.8</output>

<gadget id="calculator">7.52 + 0.8</gadget>
<output>8.32</output>

<result>8.32</result>