It takes 20 minutes to saw a steel pipe into 5 sections, so calculate how many sections can be sawed in 40 minutes.
把一根钢管锯成5段需要20分钟，照这样计算40分钟可以锯多少段．
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">20 / 4</gadget>
<output>5</output>

<gadget id="calculator">40 / 5</gadget>
<output>8</output>

<gadget id="calculator">8 + 1</gadget>
<output>9</output>

<result>9</result>