
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
Gavrila found that the front tires of a car last for 21,000 km, and the rear tires last for 28,000 km. He decided to switch them at some point to maximize the possible distance the car can travel. Find this maximum distance (in km).

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