23.5 minus the difference between 12 and 6.8, what is the difference?
23.5减去12与6.8的差，差是多少？
<gadget id="calculator">12 - 6.8</gadget>
<output>5.2</output>

<gadget id="calculator">23.5 - 5.2</gadget>
<output>18.3</output>

<result>18.3</result>