Eze's Supermarket buys a carton of biscuits for ₦4,800 and sells it at a mark-up of 25% on cost. What is the selling price of the carton?

A 25% mark-up on cost means the profit is 25% × ₦4,800 = ₦1,200. The selling price is therefore ₦4,800 + ₦1,200 = ₦6,000. Option A (₦5,800) is a common arithmetic error, option C (₦6,400) results from applying 25% incorrectly to a different base, and option D (₦3,600) represents a deduction rather than an addition.