The unit price is simply the cost for each item (or unit). The term is often used to compare the cost of the same quantity of items that come in different sizes, or it is used to determine total costs for services. For example, if a person was having a birthday party at a local restaurant for 100 guests, and each meal (unit) cost $7.50, the total cost of the celebration would be $7.50 × 100 = $750.00. Add a tip to the total (see above), and it’s easy to see why most people celebrate at home or only invite a few friends.