The milk cost $4.00 but was on sale for 1/2 off so 4*.50 = $<<4*.50=2.00>>2.00
She bought 2 pounds of bananas at $0.75 per pound so 2 *.75 = $<<2*0.75=1.50>>1.50
She had a $1.25 coupon off of laundry detergent so 10.25 - 1.25 = $<<10.25-1.25=9.00>>9.00
When you add all of her purchases together then 2 + 1.50 +3.50 + 9.00 = $<<2+1.50+3.50+9=16.00>>16.00
She paid with a $20 bill so 20-16 = $<<20-16=4>>4 left over
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