There is a box of mineral water, which is distributed to 7 groups on average. Each group gets 4 bottles, and there are 2 bottles in the box. How many bottles are there in this box of mineral water?
有一箱矿泉水，平均分给7个小组，每组分到4瓶，箱子里还有2瓶，这箱矿泉水一共有多少瓶？
<gadget id="calculator">4 * 7</gadget>
<output>28</output>

<gadget id="calculator">28 + 2</gadget>
<output>30</output>

<result>30</result>