
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
Billy wants to determine the average number of cookies in a package of cookies. He purchases 9 packages of cookies, opens them, and counts the number of cookies in each one. He finds that the packages have 9, 11, 13, 15, 15, 17, 19, 21, and an unusually low 5 cookies. Based on these observations, what is the average number of cookies in a package?

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