I decided I needed to go to Walgreen's one more time during this week's sale.
The store had a coupon inside their ad to make Reach floss $0.99 each after coupon. I then had 2 $1.50 off 2 coupons and 2 $3 off 3 coupons.
I did 4 transactions
The buy 2 get $1.50 off made 2 for $0.67 which included tax.
The buy 3 get $3 off force me to buy 4 which made them $1.34 which included tax.