
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 larger batch of packages. He buys 10 packages of cookies, but accidentally misses counting 2 of the packages. The numbers of cookies in the 8 packages he counts are 9, 11, 12, 14, 16, 17, 18, and 21 cookies. Based on these observations, calculate the average number of cookies per package assuming the two uncounted packages had an average that is the same as the counted ones.

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