
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 values of individuals in a population are arranged in ascending order as 2, 3, 3, 7, $a$, $b$, 12, 15, 18, 20 (where $a$, $b$ are in $\mathbb{N}^*$), and the median of the population is 10, determine the values of $a$ and $b$ in order to minimize the variance of this population.

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