A piece of wood is sawn into 7 sections, each sawing takes 4 minutes, how many minutes is the total time required?
一根木头锯成7段，每锯一下需要4分钟，一共需要多少分钟．
<gadget id="calculator">7 - 1</gadget>
<output>6</output>

<gadget id="calculator">4 * 6</gadget>
<output>24</output>

<result>24</result>