What is the difference between 28 minus 8 times 2.64?
28减去2.64的8倍，差是多少？
<gadget id="calculator">2.64 * 8</gadget>
<output>21.12</output>

<gadget id="calculator">28 - 21.12</gadget>
<output>6.88</output>

<result>6.88</result>