Math question involving profits

Question

the normal selling price of an article is cut by 20% ina sale. This reduces the trader's profit on the price she paid for it to 4%/ What percentage profit did she make at normal selling price

Answer 1

Let X = Normal selling price

Price after discount = X - 0.2X =0.8 X

Ley Y be the buying price of trader 

The profit originally was X-Y

New Profit = 0.8X- Y =0.04 (X-Y)

0.76X = 0.96Y

X/Y = 1.263

(X-Y)/ Y is fractional profit multiplied by 100 will give original percent profit