5x=10-2*2.3, x=how much.
5x=10-2*2.3，x=多少．
<gadget id="calculator">2 * 2.3</gadget>
<output>4.6</output>

<gadget id="calculator">10 - 4.6</gadget>
<output>5.4</output>

<gadget id="calculator">5.4 / 5</gadget>
<output>1.08</output>

<result>1.08</result>