
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
Given a certain store sells a type of fruit with a sales cost of $40$ yuan, and the monthly sales volume is $500$ kilograms when sold at $50$ yuan per kilogram. For every $1$ yuan increase in selling price per kilogram, the monthly sales volume decreases by $10$ kilograms, while the monthly sales profit reaches $8000$ yuan when the selling price per kilogram is $x$ yuan ($x > 50$), form the equation representing the monthly profit in terms of $x$.

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