If 2x+1=8, then 5.4x-2=how much.
如果2x+1=8，那么5.4x-2=多少．
<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">7 / 2</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">5.4 * (7/2)</gadget>
<output>18.9</output>

<gadget id="calculator">18.9 - 2</gadget>
<output>16.9</output>

<result>16.9</result>