Work Rate Problems

These are many students favorite word problems. The reason is that they are fairly easy to handle. Here is an example.

The relationship that underlies all work situations is

This stands for 

the amount of work you do = rate at which you work * amount of time you work for

Now when you work together with someone else, you add your work rates together. So we change the equation to 

There are lots of ways to do these problems, but these are the steps I like to use

1. Identify the rates of the different people in the problem

2. Add the rates together

3. Put them in the equation

4. Solve the equation. (There is a shortcut to solving that many students pick up on here.)
5. Make sure you show all four parts in your answer.

Let's look at some examples. 

• Example 1: Grading Tests (from above)

Now try a few on your own.

• Practice Problem 1: . 
  
   [here is the solution, don't peak until you've tried it.]
• Practice Problem 2:  
  
   [here is the solution, don't peak until you've tried it.]
• Practice Problem 3:
  
   [here is the solution, don't peak until you've tried it.] 

• Practice Problem 4:
  
   [here is the solution, don't peak until you've tried it.]