12/9+15/9=how much.
12/9+15/9=多少．
<gadget id="calculator">12 / 9</gadget>
<output>4/3 = around 1.333333</output>

<gadget id="calculator">15 / 9</gadget>
<output>5/3 = around 1.666667</output>

<gadget id="calculator">(4/3) + (5/3)</gadget>
<output>3</output>

<result>3</result>