You can cook 2 cakes at a time, and the time to cook one side is 5 minutes. If you want to cook 12 cakes, how many minutes will it take at least.
每次可以烙熟2张饼，烙熟一面的时间是5分钟，如果要烙熟12张饼，最少需要多少分钟．
<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">5 * 2 * 6</gadget>
<output>60</output>

<result>60</result>