**Problems 1-3**

Be sure to distinguish the number of each denomination of coin from the value of each denomination as shown in Example 1.
Problems 4-6

The rate upstream is the sum of the rates of the water and the boat. The rate with the wind is the sum of the rates of the wind and the plane. What is the rate downstream or against the wind? See Examples 2 and 3.
Problems 7-9

Write the given data points as ordered pairs and then graph the lines using those data points. Look for the solution at the point of intersection as shown in Example 4.
Problems 10-12

Remember, the older person has the smaller birth-year number. See Example 5.
Problems 13-18

See Examples 6-7. For these problems, read the given table to find the requested information.
Problems 19-21

You will be setting up two equations; the first if for the quantities of the entire mixture, and the second is for the part that is of concern. For example, in
Problems 22-58

To practice problem-solving you need to practice a technique, not copy the thinking process shown in the book or by another person. Think about the main idea to write down the first step, and then let the equation evolve until have a single equation with a single unknown. Solve this equation, and then use the information to answer the question that is asked.
### Note: Homework Hints are given only for the Level 1 and Level 2 problems.

However, as you go through the book be sure you look at all the examples in the text. If you need hints for the Level 3 problems, check some sources for help on the internet (see the LINKS for that particular section. As a last resort, you can call the author at (707) 829-0606.

On the other hand, the problems designated “Problem Solving” generally require techniques that do not have textbook examples.

There are many sources for homework help on the internet.

**Algebra.help**

Here is a site where technology meets mathematics. You can search a particular topic or choose lessons, calculators, worksheets for extra practice or other resources.

http://www.algebrahelp.com/

**Ask Dr. Math**

Dr. Math is a registered trademark. This is an excellent site at which you can search to see if your question has been previously asked, or you can send your question directly to Dr. Math to receive an answer.

http://mathforum.org/dr.math/

**Quick Math**

This site provides online graphing calculators. This is especially useful if you do not have your own calculator.

http://www.quickmath.com/

**The Math Forum @ Drexel**

This site provides an internet mathematics library that can help if you need extra help. For additional homework help at this site, click one of the links in the right-hand column.

http://mathforum.org/

Be sure to distinguish the number of each denomination of coin from the value of each denomination as shown in Example 1.

The rate upstream is the sum of the rates of the water and the boat. The rate with the wind is the sum of the rates of the wind and the plane. What is the rate downstream or against the wind? See Examples 2 and 3.

Write the given data points as ordered pairs and then graph the lines using those data points. Look for the solution at the point of intersection as shown in Example 4.

Remember, the older person has the smaller birth-year number. See Example 5.

See Examples 6-7. For these problems, read the given table to find the requested information.

You will be setting up two equations; the first if for the quantities of the entire mixture, and the second is for the part that is of concern. For example, in

**Problem 19**it is silver, in

**Problem 20**it is alcohol, and in

**Problem 21**, it is butterfat. See Examples 8-10.

To practice problem-solving you need to practice a technique, not copy the thinking process shown in the book or by another person. Think about the main idea to write down the first step, and then let the equation evolve until have a single equation with a single unknown. Solve this equation, and then use the information to answer the question that is asked.