There are 12 tons of goods, the first time (1/3) is transported away, how many tons of goods are left.
有12吨货物，第一次运走(1/3)，还剩下多少吨货物．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">12 * (2/3)</gadget>
<output>8</output>

<result>8</result>