Aminat bought 12 pieces of ceramics plates at ₦500 each, a pair of tongs for ₦3,500, a frying pan fo

First add up what the goods cost before tax. The plates cost 12 × ₦500 = ₦6,000. Add the tongs ₦3,500, the frying pan ₦8,500 and the food items ₦12,000.

Total before tax = ₦6,000 + ₦3,500 + ₦8,500 + ₦12,000 = ₦30,000. She actually paid ₦32,250, so the sales tax is ₦32,250 − ₦30,000 = ₦2,250.

Tax rate = (tax ÷ price before tax) × 100 = (2,250 ÷ 30,000) × 100 = 0.075 × 100 = 7.5%. Check: 7.5% of ₦30,000 is ₦2,250, and ₦30,000 + ₦2,250 = ₦32,250 ✓.