Experimental Primary School purchased a new bookshelf, each shelf is 66 cm long. One of the compartments is for dictionaries, each 3.3 cm thick, and the other is for reference books, each 2.2 cm thick. How many books can be placed in these two compartments?
实验小学购置了一个新书架，每格长66厘米．其中一格放词典，每本厚3.3厘米，一格放参考书每本厚2.2厘米，这两格共可以放多少本书？
<gadget id="calculator">66 / 2.2</gadget>
<output>30</output>

<gadget id="calculator">66 / 3.3</gadget>
<output>20</output>

<gadget id="calculator">30 + 20</gadget>
<output>50</output>

<result>50</result>