Concept:The total cost of 12 identical notebooks is divided equally among 12 books to find the cost of one book.Explanation:Let the cost of one notebook be x.Cost of 12 notebooks =54.84So, 12x=54.84To find x, divide both sides by 12:x=1254.84Now, 54.84÷12=4.57Therefore, one notebook costs GH₵ 4.57.Answer:C. GH₵ 4.57