Cool tees is having a back to school sale where all tshirts are discounted by 15%. joshua wants to buy five shirts. one costs 9.99, two costs 11.99 each, and two others cost 21.00 each. what is the total cost of the shirts including the discount? the answer is 37.98. (idk this part at all tho) joshua remembered he had a coupon in his pocket that would take an additional 30% off the price of the shirts. calculate the new total cost of the shirts including the sales tax(PLEASE HELP IM SO CONFUSED)?

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