If it takes 20 minutes to saw a water pipe with a length of 1 meter into 5 equal sections, how many minutes will it take to saw it into 10 equal sections?
将一根长为1米的水管锯成相等的5段，需要20分钟，那么将它锯成相等的10段需要多少分钟．
<gadget id="calculator">20 * 10</gadget>
<output>200</output>

<gadget id="calculator">200 - 20</gadget>
<output>180</output>

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

<gadget id="calculator">180 / 4</gadget>
<output>45</output>

<result>45</result>