
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 $40\%$ of students initially answered "Yes", $40\%$ answered "No", and $20\%$ were undecided, and at the end of the year $60\%$ answered "Yes", $30\%$ answered "No", and $10\%$ remained undecided, calculate the difference between the maximum and minimum possible values of $x\%$, the percentage of students who changed their answers.

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