
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 that the prices for direct flights between cities A, B, C, and D are directly proportional to the straight-line distances between them, with prices AB = 2000 yuan, AC = 1600 yuan, AD = 2500 yuan, CD = 900 yuan, and BC = 1200 yuan, calculate the price for the straight-line distance between B and D.

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