
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
A factory produces three different models of products named A, B, and C. The ratio of the quantities of these products is 3:4:7. Now, using stratified sampling, a sample of size $n$ is drawn. If there are 15 pieces of product A in the sample, what is the sample size $n$?

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