Rates

Two common examples of rates that occur frequently in Problem Solving include speed (i.e., miles per hour) and work (i.e., units per minute). This basic relationship may be illustrated by the basic rate formula for motion:

There are a few points to keep in minds when presented with a rate question:

• Rate questions take on different forms; some involve average rates, some involve combined rates, while many others simply test the basic rate formula. All of these questions are essentially proportion problems, and can be solved by using one of three rate formulas.
  
  
• The key to solving many rate problems is to identify the formula that corresponds to the question, and to identify what formula component you are being asked to solve for.
  
  
• Rates include units that measure quantities such as time, distance, and cost. Such units can take on different forms. Time, for instance, may be measured in seconds, minutes, or hours. It is important to keep track of units when solving rate problems, and to make sure you have converted to the appropriate unit before answering the question.

Now let's learn more about the basic rate problems.