Quantity Discount : 28.75% to 36.25% off 5+ @ 28.75% : 120.76 + 21.74 (18%) = 142.50 10+ @ 32.50% : 114.41 + 20.59 (18%) = 135 15+ @ 36.25% : 108.05 + 19.45 (18%) = 127.50