
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
In order to accelerate the digitalization of the city, a certain city plans to build a new batch of smart charging piles. In the first month, 301 charging piles were built, and in the third month, 500 charging piles were built. Let the monthly average growth rate of the number of smart charging piles built in the city be $x$. Based on the question, please write down the equation ____.

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