If you use a pan to bake 2 cakes at a time, and you need to bake both sides, each side takes 2 minutes, how many minutes will it take to bake 5 cakes?
用一只平底锅烙饼，每次能同时放2个饼，两面都要烙，每面2分钟，那么烙5个饼需要多少分钟．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">4 + 6</gadget>
<output>10</output>

<result>10</result>