In case of sales tax , we have to do addition of the tax with the total price. Price of one chicken is $12.99, so price of two chickens = 12.99*2 = $25.98 . And sales tax on each is 6% and 6% of 12.99 =0.06*12.99 = 0.7794. And on two chickens, sales tax=2*0.7794 = 1.5588 . So the total price we need to pay = 25.98+ 1.5588 = 27.5388 = $ 27.54 approx .