
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 large supermarket sells four types of dairy products: pure milk, yogurt, infant formula, and adult formula, with 30, 10, 35, and 25 different brands respectively. A stratified sampling method is used to draw a sample of size $n$ for melamine safety testing. If the number of brands of infant formula drawn is 7, find the value of $n$.

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