You are having a lemonade stand and the ingredients to make lemonade comes out to about $.08 per cup. If you sell each cup for $.75 by what percentage did you markup a cup of lemonade?

profit per cup = .75 - .05 = .67

markup = .67/.08 = 8.375 = 837.5%

or .75/.08 = 9.375
percentage markup = 9.375 - 1 = 8.375 = 837.5%