It takes 6 minutes to saw 3 sections of wood. According to this calculation, how many minutes will it take to saw 8 sections.
锯3段木材需要6分钟，照这样计算，锯8段需要多少分钟．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

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

<gadget id="calculator">3 * 7</gadget>
<output>21</output>

<result>21</result>