
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
A clothing factory produces suits and ties, with each suit priced at 400 yuan and each tie priced at 80 yuan. During a promotional event, the factory offers customers two discount options:  
① Buy a suit and get a tie for free;  
② Pay 90% of the list price for both the suit and the tie.  
Now, a customer wants to buy 20 suits and $x$ ties from the factory ($x > 20$).  
(1) How much does the customer need to pay under each plan? (Express in terms of $x$.)  
(2) If $x = 30$, which plan is more cost-effective?

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