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.
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/
Mathematics Home Page
Access the Clemens and Alcuins Library of CSB/SJU and find
one of the world's best collections of mathematical internet
sites.
http://library.csbsju.edu/rqs.phtml?subject_id=32