
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system

For 9 identical books, more than 11 rubles were paid, and for 13 of the same books, less than 16 rubles were paid. What is the cost of one book?

Present the answer in LaTex format: \boxed{Your answer}
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