Use a pan to fry pancakes, and you can put up to 4 cakes at a time. It takes 3 minutes to fry one side and fry both sides. How many minutes does it take to fry 6 cakes at least.
用一只平底锅烙饼，每次最多可放4张饼，煎熟一面要3分钟，两面都要煎，煎6张饼至少需要多少分钟．
<gadget id="calculator">3 + 3 + 3</gadget>
<output>9</output>

<result>9</result>