
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
At the beginning of the school year, $30\%$ of the 100 students in Mr. Well's class answered "Yes" to "Do you love math?", $40\%$ answered "No," and the remaining were undecided. At the end of the year, $50\%$ answered "Yes," $20\%$ answered "No," and the rest remained undecided. Calculate $x\%$, the minimum and maximum percentage of students who must have changed their answers by the end of the school year.
A) 5%
B) 10%
C) 15%
D) 20%
E) 25%

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