If it takes 4 minutes to cut a steel pipe into 2 sections, how many minutes will it take to cut it into 4 sections at this speed?
把一根钢管截成2段要用4分钟，照这样的速度若将它截成4段需要用多少分钟．
<gadget id="calculator">2 - 1</gadget>
<output>1</output>

<gadget id="calculator">4 / 1</gadget>
<output>4</output>

<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">4 * 3</gadget>
<output>12</output>

<result>12</result>