It takes 1.8 minutes to saw a piece of wood into 3 sections, how many minutes will it take to saw it into 6 sections?
一根木料锯成3段需要1.8min，锯成6段需要多少min．
<gadget id="calculator">6 - 1</gadget>
<output>5</output>

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

<gadget id="calculator">1.8 / 2</gadget>
<output>0.9</output>

<gadget id="calculator">5 * 0.9</gadget>
<output>4.5</output>

<result>4.5</result>