A rope is 12 meters long. (1/3) of it is used for the first time, and the rest (1/2) is used for the second time. How many meters are left?
一条绳子长12米，第一次用去了它的(1/3)，第二次用去了剩下的(1/2)，还剩下多少米．
<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">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (1/2)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">12 * (2/3) * (1/2)</gadget>
<output>4</output>

<result>4</result>