It takes 3 minutes to saw a piece of wood into 3 sections, how many minutes will it take to saw it into 7 sections?
一根木料锯成3段需用时间3分，锯成7段要多少分．
<gadget id="calculator">7 - 1</gadget>
<output>6</output>

<gadget id="calculator">3 * 6</gadget>
<output>18</output>

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<result>9</result>