A log with a length of 4 meters is sawed into 7 sections on average. What is the length of each section? The average time for sawing the next section is the time required for sawing into 7 sections ((())/(())).
将一根4米长的原木平均锯成7段，每段长是多少米，平均锯下一段所用的时间是锯成7段所用时间的((())/(()))．
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">4 * (1/7)</gadget>
<output>4/7 = around 0.571429</output>

<result>4/7 = around 0.571429</result>