
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]


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In Huanggang City, a supermarket offers discounts to customers under the following conditions:
① If the purchase is less than 100 yuan, no discount is offered;
② For purchases of at least 100 yuan but not exceeding 500 yuan, a 10% discount is applied;
③ For purchases exceeding 500 yuan, the first 500 yuan receives a 10% discount, and the amount exceeding 500 yuan receives a 20% discount;
Xiao Li went shopping at the supermarket twice, paying 99 yuan and 530 yuan respectively. Now, Xiao Zhang decides to buy the same amount of goods in one go that Xiao Li bought in two trips. Xiao Zhang needs to pay     yuan.

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