
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
It is known that person A alone can complete a project in 10 days, and person B alone can complete the same project in 15 days. If person A works alone on this project for 3 days and then is replaced by person B, and we assume that person B needs $x$ more days to complete it, we can set up an equation.

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