If it takes 3 minutes to saw a piece of wood into 2 pieces, how many minutes will it take to saw this piece of wood into 5 pieces?
把一根木头锯成2段要3分钟，把这根木头锯成5段要多少分钟．
<gadget id="calculator">2 - 1</gadget>
<output>1</output>

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

<gadget id="calculator">5 - 1</gadget>
<output>4</output>

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

<result>12</result>