Question: how do u do a 20 tip?
Answer: If you want to leave a 20% tip, multiply the cost by 0.20 to get the tip amount or multiply the cost by 1.20 to get the total including tip. If you want to leave a 18% tip, multiply the cost by 0.18 to get the tip amount or multiply the cost by 1.18 to get the total including tip.