A piece of wood is 10 meters long, and it takes 3 minutes to saw it into 1 meter long, how many minutes will it take to saw the wood.
一根木头长10米，把它锯成1米长，每次用时3分钟，锯完这根木头需要多少分钟．
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">3 * 9</gadget>
<output>27</output>

<result>27</result>