(B) 1.20x (C) 1.40x (D) 1.60x (E) 3.20x
--------------------------------------------------------------------------------------------------------------------------- 【答案】C
【思路】3-10每個月各運出0.5x
所以每個月存貨為 3月(3.5) 4(3) 5(2.5) 6(2) 7(1.5) 8(1) 9(0.5) 10(0)
?3.5?3?2.5?2?1.5?1?0.5??0.1?1.4
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39. 5378-!-item-!-187;#058&004220 [?]
The table shows the number of calls received by each of five operators during each of 4 one-hour periods. For which operator was the standard deviation of the numbers of calls received during these 4 periods the least?
(A) Operator A (B) Operator B (C) Operator C (D) Operator D (E) Operator E
40. 5532-!-item-!-187;#058&004320
A certain company sold 1,000 blenders at $100 each and 10 stoves at $1,000 each. If the company's total cost for the blenders and stoves was $50,000, what was the company's total gross profit on these items?
(A) $10,000 (B) $20,000 (C) $30,000 (D) $50,000 (E) $60,000
--------------------------------------------------------------------------------------------------------------------------- 【答案】E
【思路】(100000?10?1000)?50000?60000
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41. 5689-!-item-!-187;#058&004421
In the infinite sequence a1, a2, a3, . . . , an, . . . , each term after the first is equal to twice the previous term. If a5 - a2 = 12, what is the value of a1 ?
(A) 4 (B) (C) 2 (D) (E)
42. 5737-!-item-!-187;#058&004537 (-3)^(-2) =
(A) - 9 (B) -6 (C) (D) (E) 9
43. 5837-!-item-!-187;#058&004612
A college admissions officer predicts that 20 percent of the students who are accepted will not attend the college. According to this prediction, how many students should be accepted to achieve a planned enrollment of x students?
(A) 1.05x (B) 1.1x (C) 1.2x (D) 1.25x (E) 1.8x
--------------------------------------------------------------------------------------------------------------------------- 【答案】D
【思路】設錄取人數為y
y?0.8?x xy??1.25x0.8-------------------------------------------------------------------------------------------------------------------------
44. 5884-!-item-!-187;#058&004663
The arithmetic mean and standard deviation of a certain normal distribution are 13.5 and 1.5, respectively. What value is exactly 2 standard deviations less than the mean?
(A) 10.5 (B) 11.0 (C) 11.5 (D) 12.0 (E) 12.5
--------------------------------------------------------------------------------------------------------------------------- 【答案】A
【思路】13.5?(1.5?2)?10.5
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45. 5933-!-item-!-187;#058&004664
If a certain wheel turns at a constant rate of x revolutions per minute, how many revolutions will the wheel make in k seconds?
(A) 60kx (B) kx (C) (D) (E)
46. 5979-!-item-!-187;#058&004694
If a coin has an equal probability of landing heads up or tails up each time it is flipped, what is the probability that the coin will land heads up exactly twice in 3 consecutive flips?
(A) 0.125 (B) 0.25 (C) 0.375 (D) 0.50 (E) 0.666
------------------------------------------------------------------------------------------------------------------------------------ 【答案】C
【思路】丟三次要有剛好兩次頭朝上(當作正面) 所以會有三種情形: 正正反:
1111??? 2228正反正: 反正正:
1111??? 22281111??? 22283 8三個情形(“或”的觀念,所以相加)=
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47. 6025-!-item-!-187;#058&004767
A certain bakery has 6 employees. It pays annual salaries of $14,000 to each of 2 employees, $16,000 to 1 employee, and $17,000 to each of the remaining 3 employees. The average (arithmetic mean) annual salary of these employees is closest to which of the following?
(A) $15,200 (B) $15,500 (C) $15,800 (D) $16,000 (E) $16,400
------------------------------------------------------------------------------------------------------------------------------------ 【答案】C
【思路】低分區,算術平均數的題目
(14000?2)?(16000?1)?(17000?3)?15833
6------------------------------------------------------------------------------------------------------------------------------------
48. 6071-!-item-!-187;#058&004779
If x is equal to the sum of the even integers from 40 to 60, inclusive, and y is the number of even integers from 40 to 60, inclusive, what is the value of x + y ?
(A) 550 (B) 551 (C) 560 (D) 561 (E) 572
------------------------------------------------------------------------------------------------------------------------------------ 【答案】C 【思路】
X是40~60所有偶數相加
Y是40~60中所有偶數的數目(Y表示有多少個偶數) 所以
550 + 11(40,42,44,46,48,50,52,54,56,58,60) = 561
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49. 6121-!-item-!-187;#058&004785
If two of the four expressions x + y, x + 5y, x - y, and 5x - y are chosen at random, what is the probability that their product will be of the form of x^2 - (by)^2, where b is an integer?
(A) (B) (C) (D) (E)
50. 6173-!-item-!-187;#058&004786
If [?], what is the value of n ?
(A) (B) (C) (D) (E)
51. 6219-!-item-!-187;#058&004789
Which of the following is equal to the average (arithmetic mean) of (x + 2)^2 and (x - 2)^2 ?
(A) x^2 (B) x^2 + 2 (C) x^2 + 4 (D) x^2 + 2x (E) x^2 + 4x
------------------------------------------------------------------------------------------------------------------------------------ 【答案】C 【思路】
(x?2)2?(x?2)22x2?8??x2?4
22------------------------------------------------------------------------------------------------------------------------------------
52. 6267-!-item-!-187;#058&004794 If x < 0, then [?] is
(A) -x (B) -1 (C) 1 (D) x (E)
53. 6313-!-item-!-187;#058&004799
During a car trip, Maria stopped to rest after she traveled [?] of the total distance to her destination. She stopped again after she traveled of the distance remaining between her first stop and her destination, and then she drove the remaining 120 miles to her destination. What was the total distance, in miles, from Maria's starting point to her destination?
(A) 280 (B) 320 (C) 360 (D) 420 (E) 480
54. 6364-!-item-!-187;#058&004806
P, Q, and R are located in a flat region of a certain state. Q is x miles due east of P and y miles due north of R. Each pair of points is connected by a straight road. What is the number of hours needed to drive from Q to R and then from R to P at a constant rate of z miles per hour, in terms of x, y, and z ? (Assume x, y, and z are positive.)
(A) (B) (C) (D) (E)
55. 6410-!-item-!-187;#058&004809
The 15 homes in a new development are each to be sold for one of three different prices so that the developer
receives an average (arithmetic mean) of $200,000 per home. If 4 of the homes are to be sold for $170,000 each and 5 are to be sold for $200,000 each, what will be the selling price of each of the remaining 6 homes?
(A) $200,000 (B) $210,000 (C) $215,000 (D) $220,000 (E) $230,000
------------------------------------------------------------------------------------------------------------------------------------ 【答案】C
【思路】設剩下六個,每個home賣得x元
(170000?4)?(200000?5)?6x?200000
15X=220000元
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56. 6461-!-item-!-187;#058&004810
To celebrate a colleague's retirement, the T coworkers in an office agreed to share equally the cost of a catered lunch. If the lunch costs a total of x dollars and S of the coworkers fail to pay their share, which of the following represents the additional amount, in dollars, that each of the remaining coworkers would have to contribute so that the cost of the lunch is completely paid?
(A) (B) (C) (D) (E)
57. 6510-!-item-!-187;#058&004845 [?]
At the end of each year, a certain credit card company pays a bonus to each of its credit card holders based on the amount, up to $10,000, that the cardholder charged throughout the year. A 0.5 percent bonus is paid on the first $1,000 charged, a 1.0 percent bonus is paid on the next $2,000 charged and so on, as indicated in the table above. What is the maximum annual bonus, in dollars?
(A) $100 (B) $150 (C) $200 (D) $250 (E) $500
58. 6618-!-item-!-187;#058&004870 [?]
If p, q, r, and s are as shown on the number line above, which of the following products is greatest?
(A) (B) (C) (D) (E)
59. 6664-!-item-!-187;#058&004887
The cost of picture frame M is $10.00 less than 3 times the cost of picture frame N. If the cost of frame M is $50.00, what is the cost of frame N ?
(A) $13.33