She bought 2 pounds of hamburger meat at $3.50 per pound so 2*3.50 = $<<2*3.50=7.00>>7.00
The tomato weighed 1.5 pounds and cost $2.00 per pound so 1.5*2 = $<<1.5*2=3.00>>3.00
When you add up all her items she spent 7+1.50+1+3+2.50=$<<7+1.50+1+3+2.50=15.00>>15.00
Her items added up to $15.00 and she had a $1.00 coupon off pickles so 15-1 = $<<15-1=14.00>>14.00
She paid with a $20.00 bill so 20-14 = $<<20-14=6.00>>6.00 in change
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