It takes 20 minutes to saw a piece of wood into 5 sections. According to this calculation, how many minutes will it take to saw it into 8 sections?
把一根木料锯成5段需要20分钟，照这样计算，锯成8段要多少分钟．
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

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

<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">5 * 7</gadget>
<output>35</output>

<result>35</result>