# Corrections for Book 2 of Principles of Mathematics

While we worked hard to avoid errors, a few slipped through. Below is the corrected information for your reference.

Textbook
p. 81: “Subtract -3/8” should read “Subtract 3/8”.

p. 42 – Prime number wording should include the word “evenly.”

“Whole numbers that can’t be evenly divided by any whole number but themselves and 1.”

p. 50 – On both of the maps, -160o should read -150o.

p. 55 – In the first example, “Remember, UTC-0:300…” should be “Remember, UTC-03:00.”

p. 259 – In the words of the example, it should say “greater than 0” rather than “greater than or equal to 0.”

Chapter 18 (Trigonometry) – Clarification: Should you have difficulty obtaining the correct answers on your calculator, check to make sure it is not in radian (RAD) instead of degree (DEG) mode (look for a RAD or a DEG on the screen). All of the angles in the curriculum are given in degrees, so you will need your calculator in degree (DEG) mode in order to get the correct answers.

Student Workbook/Teacher Guide

Page numbers on worksheets in Chapter 1 and 2

These page numbers refer to page numbers in the Teacher Guide.

p. 76 (Worksheet 5.3B), problem 3b

Question should say “travel 15 miles” as opposed to “travel 5 miles.”

p. 164, question 5
Questions b. and c. referring back to 4a should read to refer back to 5a.

p. 371 (Answers for Worksheet 5.3A),problem 1c

The “= 1” is missing; the first ratio should also have 231 instead of 213 in the denominator.

p. 381 (Answers for Worksheet 10.5), problem 1d

Answer should be x < 55o F.

p. 381 (Answers for Worksheet 10.5), problem 2d

Answer should be x ≤ 95.

p. 398 (Answers for Worksheet 15.4, problem 3a)

The graph should look like the photo shown here. p. 413 (Answers for Quiz 1, problem 3b)

p. 414 (Answers for Quiz 4, problem 2a)

p. 416 (Answers for Quiz 13, problem 2a)

The answer should be 4, not 2.

p. 418 (Answers to Test 1, problem g)
The answer key addresses the question “How many cubit feet is the cylinder portion of these 4 silos if the cylinder portion of each one has a radius of 6 ft and a height of 32 ft?”
As the question is worded currently, the answer (p. 418) should include an additional step:

Bushels in all 4 cylinders = 14,469.12 ft3 • 12 in/1 ft • 12 in/1 ft • 12 in/1 ft • 1 bushel/2,150.42 in3 = 11,626.86 bushels

Alternately, the question can be modified to only ask for the volume in cubic feet.

Note: The conversion between bushels and cubic feet is found on p. 430.

p. 420 (Answers for Test 5, problem 3a)
The column in the table labeled b should be -600, 0, 600; the column in the table labeled p should be -300, 0, 300.

Clarification on Quizzes and Tests:
When students are told they can consult reference sheets, they are allowed to consult any reference sheet (p. 423-433) even if fewer page numbers are listed.