The engineering team repaired a 2400-kilometer highway, and completed (1/3) the first month, and how many kilometers to repair just completed half of the task.
工程队修一条2400千米的公路，第一个月修了(1/3)，再修多少千米刚好完成任务的一半．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/2) - (1/3)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">2_400 * (1/6)</gadget>
<output>400</output>

<result>400</result>