It takes 6 minutes to saw a piece of wood 18 meters long into three pieces, how many minutes will it take to saw it into six pieces?
把一根18米长的木头锯成三段要用6分钟，如果锯成六段要用多少分钟．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

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

<gadget id="calculator">6 - 1</gadget>
<output>5</output>

<gadget id="calculator">3 * 5</gadget>
<output>15</output>

<result>15</result>