Lee and his friend had a total of $10 + $8 = $<<10+8=18>>18.
The cost of the food was $6 + $4 + $1 + $1 = $<<6+4+1+1=12>>12.
The total cost, including tax was $12 + $3 = $<<12+3=15>>15.
They should have received $18 - $15 = $<<18-15=3>>3 in total.
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