You will set the equation up as part/whole = percent/100 and when you replace it with your numbers you get 60/x = 80/100 now you cross multiply and do 60*100 = 80 * x and you get 6,000 = 80x now you divide both sides by 80 then you get 75 was the original price
A negative times a negative results to a positive number, but when two negative numbers are added to each other, it still results to a negative number.
