(1.8+(5.4-3.8)/0.4)*2.5.
(1.8+(5.4-3.8)/0.4)*2.5．
<gadget id="calculator">5.4 - 3.8</gadget>
<output>1.6</output>

<gadget id="calculator">1.6 / 0.4</gadget>
<output>4</output>

<gadget id="calculator">1.8 + 4</gadget>
<output>5.8</output>

<gadget id="calculator">5.8 * 2.5</gadget>
<output>14.5</output>

<result>14.5</result>