(1/2) times of a number is 6 less than 2 times of this number, find this number. (column equation solving)
一个数的(1/2)倍比这个数的2倍少6，求这个数．(列方程求解)
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">2 - (1/2)</gadget>
<output>3/2 = around 1.5</output>

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

<result>4</result>