
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 store usually sells windows at $100 each. This week, they have a special offer where for every purchase of three windows, the customer gets one free. Dave needs nine windows and Doug needs ten windows. How much will they save if they purchase the windows together rather than separately?
A) 0
B) 100
C) 200
D) 300
E) 400

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