The percentage of the initial selling price (cost) is 100\%The percentage for the new selling price =100%−10%The percentage for the new selling price =90%If 100%= GH₵ 60090%=100% GH₵ 600×90%= GH₵ 540.00Note:1. The zeros ( {00} ) in 600 and 100 cancel each other2. 6×90=540