Errata – Equations, Inequalities, & VICs, 4th Edition

Edition 4.2

Edition 4.1

Edition 4.0

Release Date:
August, 2010

Differentiating Mark:

4.2 differentiating mark Back Cover, Bottom Right Corner

Release Date:
December 1, 2009

Release Date:
May 1, 2009

The Equations, Inequalities, & VICs Guide (192 pages) covers algebra in all its various forms (and disguises) on the GMAT. Master fundamental techniques and nuanced strategies to help you solve for unknown variables of every type.

4.1

Page Loc Description Erroneous Text Correction
65 Bot Problem #8 should include units. Problem #8: … The volume of the model is 8. Problem #8: … The volume of the model is 8 cm3.
118 Mid First sentence in the third paragraph mistakenly uses the variable z instead of y. Because we are told that x percent of z must equal y percent less than z… Because we are told that x percent of y must equal y percent less than z…
103 Mid The final paragraph of the explanation is misplaced and is not relevant to the question. The upper extreme for x is less than 6. The upper extreme for y is also less than 6, as long as it is less than x. Therefore, x + y must be less than 12. The largest prime number less than 12 is 11.  
151 Bot The last equation has an incorrect number inside the absolute value signs. Last equation:
|2(5/3) – 2| = 1/3.
|2(5/3) – 3| = 1/3.
123 Mid Answer choice A for question #6 should be (t/j + 2). (A) (t + 2)/j + 1 (A) t/j + 2
126 Bot Answer choice A for question #6 only works when j = 2. The correct answer should be (t/j + 2). Ignore the explanation.    
157 Bot There is no answer choice (E). Problem #9: … (D) 5 Problem #9: … (D) 5 (E) 7
158 Mid The variable should be x, not z. Problem #16: … what is z? Problem #16: … what is x?
93 Top In the third row of the table, the Min value of b should be -7, not 7.    
167 Top As the problem is now written, the value of k can be either 1/2 or -1/2. Nothing says that k must take on the positive value. To determine a single value of k and thus the recursive rule, we need another constraint in the problem itself. If each term is equal to the previous term times a constant number, what is the recursive rule for this sequence?

1/4 = k2
1/2 = k
If each term is equal to the previous term times a constant number, and if all terms in the sequence are positive, what is the recursive rule for this sequence?

1/4 = k2
1/2 = k or -1/2 = k
However, the requirement that all terms be positive eliminates the possibility that k = -1/2, since a negative k would force every other term to be negative. Thus, we know that k = 1/2.
195 Mid Answer choices (B) and (C) are identical. Problem #4: … (B) 100yz/x (C) 100yz/x … Problem #4: … (B) 100yz/x (C) 100y/(xz) …

4.0

Page Loc Description Erroneous Text Correction
65 Bot Problem #8 should include units. Problem #8: … The volume of the model is 8. Problem #8: … The volume of the model is 8 cm3.
118 Mid First sentence in the third paragraph mistakenly uses the variable z instead of y. Because we are told that x percent of z must equal y percent less than z… Because we are told that x percent of y must equal y percent less than z…
105 Top Diagram for #12(E) should have shaded dots at -7 and -3.    
126 Bot Answer choice A for question #6 only works when j = 2. The correct answer should be (t/j + 2). Ignore the explanation.    
123 Mid Answer choice A for question #6 should be (t/j + 2). (A) (t + 2)/j + 1 (A) t/j + 2
93 Top In the third row of the table, the Min value of b should be -7, not 7.    
103 Mid The final paragraph of the explanation is misplaced and is not relevant to the question. The upper extreme for x is less than 6. The upper extreme for y is also less than 6, as long as it is less than x. Therefore, x + y must be less than 12. The largest prime number less than 12 is 11.  
139 Mid Incorrect rephrasing. Does [the symbol] mean either of these 2 operations: addition or multiplication? Does [the symbol] mean multiplication?
146 Bot Erroneous inclusion of problem #77 from the Quant Review among VIC problem set. Quantitative Review: 1, 29, 32, 42, 52, 60, 69, 77, 85, 99, … Quantitative Review: 1, 29, 32, 42, 52, 60, 69, 85, 99, …
151 Bot The last equation has an incorrect number inside the absolute value signs. Last equation:
|2(5/3) – 2| = 1/3.
|2(5/3) – 3| = 1/3.
157 Bot There is no answer choice (E). Problem #9: … (D) 5 Problem #9: … (D) 5 (E) 7
158 Mid The variable should be x, not z. Problem #16: … what is z? Problem #16: … what is x?
167 Top As the problem is now written, the value of k can be either 1/2 or -1/2. Nothing says that k must take on the positive value. To determine a single value of k and thus the recursive rule, we need another constraint in the problem itself. If each term is equal to the previous term times a constant number, what is the recursive rule for this sequence?

1/4 = k2
1/2 = k
If each term is equal to the previous term times a constant number, and if all terms in the sequence are positive, what is the recursive rule for this sequence?

1/4 = k2
1/2 = k or -1/2 = k
However, the requirement that all terms be positive eliminates the possibility that k = -1/2, since a negative k would force every other term to be negative. Thus, we know that k = 1/2.
168 Top Incorrect definitions of variables in the equation for exponential growth. Any exponential growth can therefore be written as y(t) = y0 · kt, in which y0 represents time, k is the value of the quantity at time zero, and k represents the constant multiplier. Any exponential growth can therefore be written as y(t) = y0 · kt, in which t represents time, y0 is the value of the quantity at time zero, and k represents the constant multiplier.
177 Top 2 equations have confusing line breaks. Problem #12,
(B) (6 – 32)(8 – 42) = (-3)
(-8) = 24
(D) (2 – 3)2(2 – 4)2 = (-1)2
(-2) 2 = 4
Problem #12,
(B) (6 – 32)(8 – 42)
= (-3)(-8) = 24
(D) (2 – 3)2(2 – 4)2
= (-1)2(-2)2 = 4
190 Top Incorrect answer printed. Problem #6. 49: … Problem #6. 16: …
190 Bot Incorrect rephrasing of Statement 2 in #9. Problem #9:
Statement (2) tells is that x2 > x, so x < -1 OR x > 1. INSUFFICIENT.
Problem #9:
Statement (2) tells is that x2 > x, so x < 0 OR x > 1. INSUFFICIENT.
195 Mid Answer choices (B) and (C) are identical. Problem #4: … (B) 100yz/x (C) 100yz/x … Problem #4: … (B) 100yz/x (C) 100y/(xz) …