Art of Problem Solving AoPS Online Beast Academy AoPS Academy
ERRATA Even Math Beasts Make Mistakes

Below is a list of errors that have been found in the Beast Academy books.

Errors noted in light gray text are from previous editions and have been corrected in the most recent printing.

If you find an error that is not currently listed, please click here to let us know.

Guide

On page 30, the section title should say "Regrouping & Breaking."

On page 38, in the second panel, Lizzie adds 62+70 and gets 135. Oops! This should be 132.

On page 55, the first line of the Play instructions should say, "Players take turns placing one of their own coins on the number line until the number line is full."

Practice

On page 57, problem 83 should begin "The eight numbers below use only the digits 2 and 9."

Practice

On pages 50 and 52, the Guide Pages referenced at the bottom of the page should be 50-54, not 44-49.

Guide

On page 56, Winnie switches 77 and 78. She should say "Subtracting 78 is almost the opposite of adding 77."

Practice

On page 76, we circled 19+12=31 where we should have circled 19+37=56.

On page 147, the answer to problem 126 should conclude with, "We explore why this is impossible in problems 129-132."

There are no known errors for this book.

Practice

On page 79, problem 57 should begin "Three regular hexagons..."

On page 92, problem 111 should end with the word polygons, not rectangles.

Practice

On page 120, the last sentence of the solution to problem 124 should begin "The area of a square..."

On page 120, the solution to problem 130 assumes that 0 is not used. Since 0 is often considered a whole number, we can get 0+2+4+10=16 if we use 0.

On page 72, problem 130 is ambiguous (depending on whether or not zero is considered a whole number). If you consider 0 a whole number, the correct answer is 16 (0+2+4+10, for example).

On page 86, problem 84 should ask "How many points did the koombas score?"

On page 88, problem 91 has the dimensions of the third rectangle reversed. The height should be 700, and the width should be 270.

Guide

On page 20, the second panel lists 4 equations. The second equation is listed as 10+n=3, but should have been 10-n=3.

On page 20, the fourth equation should have been 11+n=14 to match the equation Grogg solves on the next page.

Practice

On page 58, it says "Use the following for Problems 101 and 102." It should say "...Problems 103 and 104."

On page 61, in the example, the second explanation has two 11's that should be 18's. It should say, "(10×18)÷7 has the same remainder as (3×4)÷7." The last sentence of the solution should read, "So, (10×18)÷7 has remainder 5."

On page 66, there is a missing "that" in problem 149. The question should read, "What is the side length of an equilateral triangle that has the same perimeter as the nonagon?"

On page 70, it should recommend that the book be used with Guide 3C, not 3A.

On page 92, our chart incorrectly lists September as having 31 days. September has 30 days.

On page 102, the hint to problem 117 should replace the numbers 183, 184, and 185 with 187, 188, and 189, respectively.

On page 123, the solution to problem 104 should end with 117÷9=13, not 17÷9=13.

On page 124, the solution to problem 117 should read (187+188+189)÷75, not (183+184+186)÷75.

On page 129, the solution to problem 146 says that 72÷6 has remainder 6. It should say that 72÷6 has remainder 0.

On page 128, the solution to problem 144 should say, "We find the remainder when each number is divided by 5".

Guide

On page 48, in panel 4, Winnie should have said, "We can write 15/16 and 29/32 with the same denominator!"

On page 69, the first balloon says "...40,000 360,000, coins." It should just say "...40,000 coins."

On page 70, Winnie should have said "...it's helpful to use two numbers..." (not "to" numbers).

On page 88, Captain Kraken's speech balloon is the wrong color.

Practice

On page 40, we misspelled denominators as denominatators in the first balloon. Oops!

On page 54, problem 58 should be 866+1,671=2,537.

On page 60, problem 88 incorrectly states that 1600-1000=700!? Of course, we meant to say 1600-1000=600.

On page 64, the worked example should state, "Since 268 is greater than 250 and 765 is greater than 750..." (765 replaces 768).

On page 106, the hint for problem 148 is from a discarded problem about teeth brushing.

On page 132, in the solution to problem 32, the last sentence should say that we round 23 5/9 up to 24.

On page 138, the solution to problem 101 should read, "333 is close to 320..."

On page 138, in the solution to problem 104, both 6,273's should be 6,237's.

On page 147, the solution to problem 27 incorrectly lists the units as 128 sq in. The units should be sq cm.

Guide

On page 11, the Headmaster should have said that some of the topics go well beyond what is typically taught in a fourth grade math class.

On page 29, the stop sign should have a question mark instead of a period.

On page 30, Ms. Q. should have asked, "Now, who wants to make a kite?"

On pages 35-36, the very center of the compass rose should be all one color. As-is, the compass rose has rotational symmetry of order 2.

On page 77, evaluate is misspelled in Lizzie's writing in panel 1.

On page 79, the first rule lists 6^2+5^2+1^2=52. However, 6^2+5^2+1^2=62.

Practice

On page 29, Symmetry Defense is much more interesting if the 'Moving' round begins with Player 2. As written in the first printing, Player 1 should be able to win every game.

On page 81, the example instructions should say, "...as the square of a number," not "...as a the square of a number."

On page 88, in the 8th paragraph, the last sentence should read 13^5 × 13 = 13^6 ends in 9.

On page 103, the hint given to problem 60 should say "Angle PQR?" not PRQ.

On page 104, the hint given to problem 139 should say "...yzzz is between 4,000 and 6,000."

On page 107, the solution to problem 7 should state that "Only the third diagram shows one point."

On page 128, the answer given to problem 22 should be 1232, not 1234.

On page 136, in the solution to problem 81, the answer given to 68×75 should be 5,100, not 5,000.

On page 146, the solution given to problem 139 should say "...yzzz is between 4,000 and 6,000."

On page 152, in the solution to problem 23, it should say that "...3^2 is the product of two 3's..."

On page 154, in the solution to Problem 51 the parentheses are wrong in the next-to-last paragraph. (3×4×5)+2 should be 3×(4×5+2).

On page 158, the solution to problem 88 should read "Then, since 4=2×2," not "4=3×2."

On page 160, problem 108 should say that 26^3=(2×13)^3.

On page 166, in problems 144 and 145, the final list of answers includes 1,000 instead of 10,000.

Guide

On pages 23-24, the words ketchup and mustard are switched in multiple panels.

On page 24, in the last blue speech balloon, the words ketchup and mustard are switched.

On page 39, Winnie lists the pair of Winnie and Lizzie as "A&L." It should say "W&L."

On page 49, the stop sign should read, "Is there a number you can multiply by 0 to get 6?" (the 0 and 6 are switched).

On page 53, in Ms. Q.'s first speech balloon, there is a 0 missing. It should read, 3,500,000.

Practice

On page 18, problem 41 should read, "...flips a coin six times and records the results."

On page 22, the example should read, "...a survey of 19 pet owners."

On page 24, we omitted a word. Grogg's mom should have counted "...11 monsters that have no wings and no tail."

On page 92, in the first step of the example explanation, it should read, "We draw a triangle to represent the tent,..."

On page 108, in the solution to problem 57 below the first diagram it should read, "...we first subtract 8 from each number..."

On page 126, the solution to problem 144 has a 1,625 in the final paragraph that should be 1,624.

Guide

On page 18, in the bottom panel, Alex should have said 71 instead of 73.

On page 25, there is a square in the first chart that should be green. Can you find it?

On page 88, in the last panel, Winnie's speech balloon is the wrong color.

Practice

On pages 50 and 51, problems 80 and 82 both say, "One the line below,..." Both should read "On the line below,...".

On page 60, problem 134 should have read 7-9/10 minus 2-3/10 to match the solution given.

On page 65, problem 167 has an extra of in the question "How many of ounces of...".

On page 144, the answer to problem 182 should read 16 meters.

Guide

On pages 49, 60, and 68, the red boxes giving Practice page recommendations (39-49, 50-61, and 62-71, respectively) are missing.

On page 111, in the index entry under number line, the word multiplying is misspelled.

Practice

On page 19, the entry blank for problem 76 should not include n=.

On page 70, problem 200 should have 2.97, not 1.98 in the problem statement. The problem is impossible as written.

On page 98, problem 105 should have read, "What is the probability that both jellybeans are green?"

On page 134, the solution to problem 200 should have 2.97, not 1.97, in every instance.

Practice

On page 34, problem 134 should say, "The area of the base of the decagonal prism..." The prism's base is a decagon, not a dodecagon.

On page 36, problem 150 should say, "Both faces of the 4×5 block were painted red." The block is not a cube.

On page 100, problem 176 should end in a question mark, not a period.

On page 105, the Chapter 3 heading should be Expressions & Equations (not Integers).

Guide

On page 52, the stop sign at the bottom of the page should ask for the GCF of 2,772 and 3,564 (not 3,584).

On page 66, the common primes in the overlapping section of Grogg's Venn diagram are 2, 2, and 3. He inexplicably multiplies 2×3×3=18 to get the GCF of 84 and 108. He should have multiplied 2×2×3=12.

On page 81, the stop sign should ask for the smallest denominator of 7/10 + 2/15.

On page 98, Grogg's last balloon should read 23/20÷22/15, not 23/20÷15/22.

On page 107, Alex should not have included 11 and 25 as a pair of primes (since 25 is not prime). Even the brightest little monsters at Beast Academy make mistakes sometimes.

Practice

On page 29, problem 112 should have an l in the word "monthy."

On page 64, it should say, "Use this Practice book with Guide 5B..." (not 4C).

On page 74, the example is broken. In the top four diagrams, the sum of the bottom row is 1/4, which makes the puzzle impossible. In the bottom two diagrams, the sum of this row is 3/4, which creates several possible solutions.

On page 76, the example solution should state that 2/1 is greater than 1.

On page 120, the solution to problem 16 should include 11 in the list of smallest factors of 2,772.

On page 146, in the solution to problem 85, the fraction 6/15 should be 6/45.

Guide

On page 58, Grogg's question should end in a question mark.

Practice

On page 19, problem 86 should ask for the common difference of an eight-term sequence.

On page 42, the second paragraph of the first Example solution has the words juice and soda switched.

On page 61, problem 127 includes the word "can" twice.

On page 103, problem 200, the 83/11 clue should be replaced with 31/9. The solution will reflect this change.

On page 122, the solution to problem 76 should include the sequence 45-49-53-57-61.

On page 134, the solution to problem 150a should be 32, 24, 43, 35, 54, 46, 65, 57, 76, 68.

Practice

On page 30, problem 150 should ask, "How many kilometers did Anna run?"