GRE-Math-Questions-to-Know-by-Test-Day-2nd-Edition_pag236

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Answers ‹ 227
379. (B), (D) (A) = ≠1 1
4
% 1.25% 125%; (B) 1.25 = 125%; (C) 0.125 = ≠12.5% 125%; 
(D) = =5
4
1.25 125%; (E) ≠12.5% 125% 
 Tip: You should eliminate (A), (C), and (E) right off because 125% is greater than 100% 
(= 1). The numbers in these answer choices are less than 100%.
380. (D), (E), (F) If a 0.5 0.5= , then ≤a 0.5. Only (A), (B), and (C) satisfy this condition. 
381. (A), (C), (D), (F) (A) − ≈ − = −33 32 25 5 ; (B) − = −17
4
4.25; (C) π− ≈ −3.14; 
(D) =8 23 ; (E) 5 , between =4 2 and =9 3; (F) π ≈ =
2
3.14
2
1.57; (G) =13
3
4 1
3
 
382. (A), (C), (E) Eliminate (B) and (D) because each of these numbers is the product 
of 2 and an even number. (A) 6 is ×2 3 (an odd number) and it is an even multiple of 3; 
(C) 18 is ×2 9 (an odd number) and it is ×6 3, an even multiple of 3; (E) 30 is ×2 15 (an 
odd number) and it is ×10 3, an even multiple of 3. 
383. (B), (C), (E) Eliminate (A) and (D) because 41 and 37 are prime numbers, so a cannot 
be a positive divisor of either −41 or 37. To check the other answer choices, use the divisibility 
property that if an integer divides both b and c, then it divides +bx cy, where x and y are any 
integer. (B) ⋅ − ⋅ = − = −1 30 1 42 30 42 12, so a divides −12; (C) − ⋅ + ⋅ = − + =1 30 1 42 30 42 12, 
so a divides 12; (E) ⋅ + ⋅ = + =2 30 1 42 60 42 102, so a divides 102.
384. (A), (C) List the possibilities:
 1 five-dollar bill and 3 one-dollar bills = $8 (A)
 2 five-dollar bills and 2 one-dollar bills = $12
 3 five-dollar bills and 1 one-dollar bill = $16 (C)
 Note: $4 (4 one-dollar bills) and $20 (4 five-dollar bills) are not possibilities because the 
question states that Kobe has five-dollar and one-dollar bills.
385. (B) Make a sketch. The contractor erected 5 flags (B).
50 feet50 feet50 feet50 feet
200 feet
386. (C), (E) = +m q17 3, where q is an integer. Check the answer choices. (A) = +q73 17 3 
implies q is not an integer; (B) = +q240 17 3 implies q is not an integer; (C) = +q258 17 3 
implies q = 15; (D) = +q274 17 3 implies q is not an integer; (E) = +q292 17 3 implies q = 17.
387. (D) Only (D) must be true. (A) Not true if ≤x 0; (B) Not true if