Father, mother and Xiaoming each eat one cake, the chef can only bake two cakes at a time, both sides need to be baked, each side needs 3 minutes, how many minutes can it be cooked.
爸爸、妈妈和小明每人吃一张饼，师傅每次只能烙2张饼，两面都要烙，每面需要3分，多少分钟能烙熟．
<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<result>9</result>