1+2*3/(4+5)*6=how much.
1+2*3/(4+5)*6=多少．
<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">3 / 9</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">2 * (1/3) * 6</gadget>
<output>4</output>

<gadget id="calculator">1 + 4</gadget>
<output>5</output>

<result>5</result>