Test Prep Math Errata


Test Prep Math @ August 2017
I think Edition 3 is almost error free at this point.  I noticed a single error in one of the quantitative questions in Section 2, but I'm still not 100% sure it's an error but I fixed it anyway.  If these problems were straight forward and clear, they wouldn't produce cognitive growth.  That's the secret to the whole book.

Section 3 is brand new.  Section 3 went through a more rigorous review, but editors are nearly useless so I did it myself.  5 times.  And 5 times I went back and forth on some problems, so it's likely I'll have to do more elaborating than correcting even thought the solutions contain thorough explanations.  You have free access to the author by posting a question below.  No other book can say that.  So post away.  I'd like to remind everyone that Section 1 is the most awesome thing you could do for your child's future, unless your child wants a PhD in physics or chemistry, in which case Section 2 is the most awesome thing you can do, so please finish these sections if you are tempted to jump right into Section 3 because you need to get past a GAT test first.  Also, at least 10 or more Section 1 problems are required (maybe 20) before the average bright student is ready for the other sections.


Errata Test Prep Math Level 2 (Edition 2)
These 2 were fixed in February 2017.
  • On Question #54, the change in the difference is a decrease of 2.  The solution says that there was no change, but it's because I can't do my own convoluted problems.
  • Question #53 is also incorrect.  There's nothing fancy happening on this problem and it's the easiest one in the book.
These 3 haven't been fixed yet and I' currently on question 67 as I do these again.  I can't believe how similar these questions are to mini-SAT reading comprehension questions, which happens to be our current exercise at home. I spent two years rearranging and reformulating the structure of each question.  Good for the question, but bad for the solutions.
  • Question 62 There are 19 - 13 = 6 band member who don't play instruments, making the final answer 6 + 7 = 13.
  • Question 63: Yani earned 20/4 = 5 + 7 = 12 dollars, and if Mallory has 16, he needs to sell  16 - 12 + 1 = 5 more commemorative cups.
  • Question 64: In the bonus question, 3 of the girls didn't turn in registration form,, which means 13 - 3 - 4 = 6 were missing forms.
Errata For Test Prep Math Level 3 - Edition 3
This edition introduces the visual spatial section of 102 problems harder than anything on a cognitive skills test.  It just came out in June 2017, so I expect the errata page to fill up in the next year.   Coaching with these problems went well, but when I reviewed the complete solutions 3 times before publication, my brain was just spinning.  The editors (journalist types) were useless as well in actually solving the problems.

Errata For Test Prep Math Level 3 - Edition 2


  • The answer to 12-A in Section 2 is 32 which is not listed.


Errata For Test Prep Math Level 3 - Edition 1
  • Question 2. There were 10 + 6 = 16 marchers with the second float and therefore 16 - 10 = 6 fewer marchers near the 1st float.
  • Question 15.  For the bonus question, assuming 28 vehicles, there were 4*24 + 8 = 104 wheels. Assuming 22 vehicles, there were 80 wheels.
  • Question 18, Bonus Question.  3 Stones are needed starting with 11 frogs and the best solution strategy is to throw one stone at a time and find out what happens.
  • Question 27: Bill starts at 8:00 – 50 minutes = 7:10.  Ava starts at 8:15 – 55 minutes = 7:20.  Bill starts 7:20 – 7:10 = 10 minutes earlier.
  • Question 33: Bus #103 is the best because Bill is always late and will miss bus #311. 
  • Question 43.  Veronica needs 25 / 5 = 5 balloons.  In one addition, the answer is 5/5 = 1 but I subsequently changed the problem.
  • Question 44.  If she gets paid $1 every day for 2 weeks, she will earn $14.  If she takes the other deal, she gets 2 * 2 * 2 * 2 * 2 * 2 * 2 quarters, or 128 / 4 = $32 dollars.  She should take the doubling deal.
  • Question 48:  We're still arguing whether the break after the last class is really a break.  So it's either 1:35 (with break) or 1:30 (no break)
  • Question 52 - The solution neglects 16 years of school through college + Kindergarten so this will make Ike's parents 38 + 1 + 1 + 16 + 16 = 72
  • Question 55 - I changed my approach to doing this solution after working with kids.  Here's the full solution.  This question holds an important math relationship that seems trivial but it is not trivial.
The first rubber band string is 20 inches long, requiring 20 / 2 = 10 rubber bands, plus an extra rubber band for a total of 11.  Does the second approach require 10 + 1 + 10 + 1 = 22?
Bonus Question:  The punchline is that a triangle drawn within a square that has its based on one short side and its apex on the other short side will have 2 sides that are longer than then long sides of the rectangle.   I’m 97% sure this relationship will reappear in a geometry proof someday.
Therefore, the second option requires 23 rubber bands and the difference is 23 – 11 = 12.

  • Question 61: I reworded the  bonus question after doing algebra proofs with my older child, and again it's a subtle but extremely important math relationship in bold below. Bonus Question: Notice that Buck is always trained for less time than Slo Mo, less in the 10 weeks, and less in the next 20. Without any calculation at all, we know that Buck is always trained less.  Less plus less = less
  • Question 64 has a typo.  50 - 24 should read 50 - 26 = 24.
  • Question 70.  The solution is correct but I thought I'd point out something that I didn't mention in the first edition.  Reading comprehension scores saw a big jump after we did this book.  This shouldn't come as a surprise to anyone by this point in the book,   Complicated reading comprehension questions don't require as much brainpower as TPM questions. 
  • Question 71: First, what does the year “right between the first and last voyage” mean?  The middle year between 1710 and 1718 is 1714, which is a good year to pick.  1716 is also a good year to pick, but not as correct.  Since it is June, 2035, and we are going back to 1714, this is 3 century buttons (300), plus 2 decade buttons (20), plus 1 year buttons.  Month buttons are not necessary.  That is a total of 6.  If your child is not totally overwhelmed by this problem, they will figure out that they have to press a button to actually make the machine take them back in time, but I'm not counting on this, so I created the bonus question.
  • Question 72: This time they have to press the century button 3 times to get them back to 1722, and then the year button 5 times to get back to 1717, followed by 8 month buttons and  8 day buttons.  That’s 24, plus the red button for 25.
  • Question 79 - there are 27 ants in the sand above the tunnels, not 26, so the answer is 90 ants in the 2nd ant farm. 
  • Question 97:  There are 31 gloves of each color, and assuming matching pairs, this is 15 sets.  You have to assume matching pairs because this is not a graduate level probabilities course.   This means 13 leprechauns can be fitted with gold gloves and hats, and 15 leprechauns can be fitted with blue gloves and hats, so 28 will have matching sets.  If there were 31 caught, 3 will not have matching sets.  If you came up with an answer to the prior problem where only 30 were caught, then 2 will not have a matching set of gloves and hats.
  • Question 99:  The question should read "tablespoon" instead of "teaspoon", or else the fairies are going to be producing the max # of teaspoons on the 3rd day and this is a corner solution.

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