If it takes 6 minutes to saw a piece of wood into 3 pieces, how many minutes will it take to cut it into 4 pieces?
把一根木头锯成三段需要6分钟，如果把它据成4段需多少分钟．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

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

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

<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<result>9</result>