※ 引述《amateurptt (剩自己了...)》之銘言： : hjjh : 51. Circular gears P and Q start rotating at the same time at constant speeds. : Gear P makes 10 revolutions per monute, and gear Q makes 40 revolutions per : minute. How many seconds after the gears start rotating will gear Q have : made exactly 6 more revolutions than gear P? : (A)6 : (B)8 : (C)10 : (D)12 : (E)15 : ans:D P一秒轉1/6圈，Q一秒轉2/3圈 故每秒Q比P多走1/2圈 --> 12秒後就多走6圈 : ============================================================================ : 57. If n is a multiple of 5 and n = (p^2)q, where p and q are prime numbers, : which of the following must be a multiple of 25? : (A)p^2 : (B)q^2 : (C)pq : (D) (p^2)(q^2) : (E) (p^3)q : ans:D 不知道5這個因數是在p還是在q裡頭 要保證一定是25的倍數，只好讓p跟q都平方了 : ============================================================================= : 62. Alice's take-home pay last year the same each month, and she saved the : same fraction of her take-home pay each month. The total amount of money that : she had saved at the end of the year was 3 times the amount of that portion of : her monthly take-home pay that she did not save. If all the money that she : saved last year was from her take-home pay, what fraction of her take-home : pay did she save each month? : PP中並無選項出現 但是我還是想要知道解題思路 謝謝~ 一年存的錢 = 3 * (每個月花的錢) 3x x --> 每個月存的錢 = 3x/12 = x/4 --> 每個月存的錢：花的錢 = 1:4 ，存錢占月薪1/5 : ============================================================================== : 63.For which of the following function is f(a+b) = f(a)+f(b) for all positive : numbers a and b? : (A) f(x)=x 2 : (B) f(x)=x+1 : (C) : (D) : (E) f(x)=-3x : ans:E : 這一題我也是算E, 但是A選項也通呀! 排版錯，A選項是平方 : ============================================================================ : 71. On July 1 of last year, the total number of employees at Company E was : decreased by 10 percent. Without any charge in the salaries of the remaining : employees, the average ( arithmetic mean ) employee salary was 10 percent : more after the decrease in number of empolyees than before the decrease. : The total of the combined salaries of all of the employees at Company E after : July 1 last year was what percent of that before July 1 last year? : (A) 90% : (B) 99% : (C) 100% : (D) 101% : (E) 110% : ans:B 7/1後，人數變90%，薪水變110% 所以是原來的 0.9*1.1 = 99% : 這題讓我很confuse 希望板大熱心提供解題方法 : 謝謝大家~~ --

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