title: How to round an answer to a mathematical equation
body: <p>All-
  I have an app in which the users inputs data such as the cost of a dinner bill and the tip percentage and the number of people. The app than takes the numbers and outputs the total bill cost and the amount each person has to pay. I am almost there but when the user inputs numbers that don't work well I get outputs like $23.576 or $34.999999999. My question is how do I make the app round the two output answers to two decimal places ($55.349 goes to $55.35)?
  Thanks in advance!  </p>