"오십 퍼센트의 할인"
Translation:Fifty percent discount
Not exactly since 할인 refers to more of a discount that is 50% than saying "50% will be cut off."
You could have a meaning more similar to 50% off if you say 50% 깎다, but usually thats used as a sentence like "50프로 깎았다," (the price was cut 50%) "50프로 깎아줄게" (i'll cut the price 50% for you
Usually in stores you could see signs saying 50% 할인 or even just the word "sale" in big capital letters with the discounted price or the percentage