It is known that 6x+4=20, then 3x+4=how much.
已知6x+4=20，那么3x+4=多少．
<gadget id="calculator">20 - 4</gadget>
<output>16</output>

<gadget id="calculator">16 / 6</gadget>
<output>8/3 = around 2.666667</output>

<gadget id="calculator">3 * (8/3)</gadget>
<output>8</output>

<gadget id="calculator">8 + 4</gadget>
<output>12</output>

<result>12</result>