
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
The selling price of a certain fruit is $a$ yuan per kilogram $(a \leqslant 30)$. If $3$ kilograms of this fruit are purchased with a $100$ yuan bill, the change should be ______ yuan (expressed as an algebraic expression involving $a$).

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