
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
The sum of the areas of the four smaller rectangles is equal to the area of the large rectangle. Given that the areas of three of the smaller rectangles are 6, 15, and 25, find the area of the fourth smaller rectangle.

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