Nomenclature of Nonacyclo Compound

I can't understand which are the nine cycles in this compound. It seems to me that there are 11 faces and thus 11 cycles. And what is the numbering of the carbon?
[![  1: https://i.stack.imgur.com/5OpfI.jpg](https://i.stack.imgur.com/fa2eA.jpg)](https://i.stack.imgur.com/fa2eA.jpg)


Source: Advanced Organic Chemistry by Jerry March.




The concise Comment of @Loong establishes the presence of nine rings in structure **1**, which has the molecular formula $\ce{C20H24}$. The most saturated alkane with 20 carbons is $\ce{C20H42}$. If one subtracts the former formula from the latter one, the result is 18. What does this number mean? It is the number of hydrogen atoms (**two**) that must be removed from the acyclic alkane to form a new C-C bond (**one**). Thus, 18/2=9 rings (and/or multiple bonds).  

In the first example, five arbitrarily selected bonds (in red) in **1** are "cut" and two hydrogen atoms added resulting in tetracycle **2**. Again, four arbitrary bonds in **2** are cut to afford the $\ce{C20H42}$ acyclic alkane **3**. Similarly, the sequence **1'** $\Rightarrow$
**4** $\Rightarrow$ **5** is equally applicable. Bonds must be selected to maintain the $\ce{C20}$ structure.  

Other resources on this topic and links are available [here](https://chemistry.stackexchange.com/questions/172453/degree-of-unsaturation-or-index-of-hydrogen-deficiency/172466#172466) on ChemSE.


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