Two pieces of snickers cost $1.5 x 2 = $<<1.5*2=3>>3.
One pack of M&M's costs $3 so 3 packs cost $3 x 3 = $<<3*3=9>>9.
The total amount that she needs to pay is $3 + $9 = $<<3+9=12>>12.
Julia gave the cashier $10 x 2 = $<<10*2=20>>20.
So, her change is $20 - $12 = $<<20-12=8>>8.
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