5 students lined up for lunch, and Yingying was the first one. It took her 2 minutes to get lunch. How many minutes did the students behind her wait in total?
5个同学排队打饭，迎迎排在第一位，她打饭花了2分钟，她后面的同学一共等待了多少分钟．
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">2 * 4</gadget>
<output>8</output>

<result>8</result>