There are 240 pens, exactly 4 boxes can be placed, each box has 2 layers, how many pens are placed in each layer on average? (answer in two ways)
有240支钢笔，正好可以放4个盒子，每个盒子有2层，平均每层放多少支钢笔？(用两种方法解答)
<gadget id="calculator">240 / 4 / 2</gadget>
<output>30</output>

<result>30</result>