It takes 16 minutes to saw a piece of wood into 5 sections, how many minutes will it take to saw it into 8 sections?
一根木材，锯成5段需要16分钟，锯成8段需要多少分钟．
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">16 / 4</gadget>
<output>4</output>

<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">4 * 7</gadget>
<output>28</output>

<result>28</result>