※ 引述《chia1985 (chia)》之铭言： : 2-29 : if 10^50-74 is wriiten as an integer in base 10 notation, : what is the sum of the digits in that integer? : A.424 : B.433 : C.440 : D.449 : E.467 : Answer: C 9999999999999999...........26 48 * 9 + 2 + 6 = 440 : 2-30 (有图) : In the figure, exch side of square ABCD has length 1, : the length of line segment CE is 1, and the length of line segment BE : is equal to the length of line segment DE. What is the area of the : triangular region BCE? : A. 1/3 : B. [2^(1/2)]/4 : c. 1/2 : D. [2^(1/2)]/2 : E. 3/4 : ANSWER: B 我算是C....不过有用到余弦定理 : 3-14 : How many seconds will it take for a car that is traveling at a : constant rate of 45 miles per hour to travel a distance of 22 yards? 220yard吧?! : (1 mile = 1,160 yards) 1760吧?! : A. 8 : B. 9 : C. 10 : D. 11 : E. 12 : Answer: C 改起来就没错了.... 45m/1h= 45 * 1760 / 3600 (单位:yard/秒) = 22y/s 220/22=10秒 : 3-15 : (DS)If n and k are positive integers, is n/k an even integer? : (1) n is divisible by 8. : (2) k is divisible by 4. : Answer: E 8d/4g = 2d/g 是不是偶数要看 举例一下d=2 g=2 就是偶数 d=3 g=2就是奇数 E : 3-18 : Last year the price per share of Stock X increased by k percent : and the earnings per share of Stock X increased by m percent, : where k is greater than m. By what percent did the ratio of : price per share to earnings per share increase, in terms of k and m? : A. k/m % : B. (k-m) % : C. [100(k-m)]/(100+k) % : D. [100(k-m)]/(100+m) % : E. [100(k-m)]/(100+k+m) % : Answer: D 这种题目就是考英文 一句一个式子 Xp -> Xp(1+k%) Xe -> Xe(1+m%) 问的是 Xp/Xe -> [Xp(1+k%)]/[Xe(1+m%)] 增加多少%? 假设增加n%.....表示 Xp/Xe *(1+n%) = Xp(1+k%)/Xe(1+m%) =>1+n% = 1+k%/1+m% =>(100+n)/100 = (100+k)/(100+m) 100(100+k) 100^2 + 100k - 100^2 - 100m 100+n = ____________ => ______________________________ = n 100+m 100+m 100(k-m) => n = ________________ 100+m 最後把假设的% 就解了 : 以上几题想不到solution 希望有高手可以指引一下^^ : 谢谢~ -- 第一句我最喜欢的是 Its cruel, its tough, its business..... 第二句最中肯的是 钱不是万能, 但是没有钱就万万不能..... You got to know both of them!!!~~~ --

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