GRE-Math-Questions-to-Know-by-Test-Day-2nd-Edition_pag170

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51. (B) In a geometric sequence, you multiply by a common ratio, r, to get the next 
term. From the consecutive terms 8 and 16, r = =16
8
2. Using 2 as the common ratio, the 
terms are 2, 4, 8, 16, 32, 64, 128. Thus, the list includes 7 terms. Hence, Quantity B is 7. 
Quantity A is + = + =a a 2 4 61 2 . Quantity B is greater.
52. (A) Let f = the number of female members in the club and m = the number of male 
members in the club. The question information yields two equations: (1) + =f m 56 and 
(2) +
+
=m 4
56 4
5
12
. Solve (2) for m.
 +
+
=m 4
56 4
5
12
 
 + =m12( 4) 5(60) 
 + =m12 48 300 
 =m12 252 
 =m 21 
 Substituting =m 21 into (1) gives + =f 21 56, =f 35 (Quantity A). Quantity A is 
greater. Tip: Be sure to read the question carefully. Quantity A is the number of female 
members in the club, not the number of male members.
53. (C) Quantity B is:
+ + +
+
x x x
x
1
1
3 2
 = + + +
+
x x x
x
( 1) ( 1)
1
2
 = + +
+
x x
x
( 1)( 1)
1
2
 = +x 12 
 The two quantities are equal. Select (C).
54. (C) Let s = the amount of money Sofía has and z = the amount of money Zayn 
has. The question information yields two equations: (1) − = +s z$5 $5, − =s z $10; and 
(2) + = −s z$5 2( $5), + = −s z$5 2 $10, − = −s z2 $15, − + =s z2 $15. Adding (1) − =s z $10 
and (2) − + =s z2 $15 gives =z $25. Thus, Zayn has $25. Then − =s z $10 implies −s $25 = 
$10, s = $35. So Sofía has $35 (Quantity A). Quantity B is + =$25 $10 $35. The two 
quantities are equal. Select (C).
55. (B) Substitute = −t s2 1 into the first equation and solve for s and then t.
 + =s t4 3 27 
 + − =s s4 3(2 1) 27 
 + − =s s4 6 3 27 
 =s10 30 
 =s 3 (Quantity A)
 = − = − =t s2 1 2(3) 1 5 (Quantity B)
 Quantity B is greater.
06_McCune_Answer.indd 161 2/21/22 4:44 PM