
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
Xiaoming's distance from home to school is 3500 meters. He leaves home at 7:30 AM and walks to school, arriving between 8:10 (including 8:10) and 8:20 (including 8:20). If we denote Xiaoming's walking speed as $x$ meters per minute, calculate the range of Xiaoming's walking speed.

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