If 3a+7=9, then 7a-(2/3)=how much.
如果3a+7=9，那么7a-(2/3)=多少．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">7 * (2/3)</gadget>
<output>14/3 = around 4.666667</output>

<gadget id="calculator">(14/3) - (2/3)</gadget>
<output>4</output>

<result>4</result>