Re: [計量] GWD 2-29 2-30 3-14 3-15 3-18

[giyoshi (HAKUNA MATATA)]

※ 引述《chia1985 (chia)》之銘言：
:  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 (有圖)
:  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....不過有用到餘弦定理

:  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
改起來就沒錯了....

45m/1h= 45 * 1760 / 3600 (單位: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
是不是偶數要看 舉例一下d=2 g=2 就是偶數
d=3 g=2就是奇數

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

這種題目就是考英文
一句一個式子

Xp -> Xp(1+k%)
Xe -> Xe(1+m%)
問的是
Xp/Xe -> [Xp(1+k%)]/[Xe(1+m%)]  增加多少%?
假設增加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

最後把假設的% 就解了


:  以上幾題想不到solution 希望有高手可以指引一下^^
:  謝謝~

--
第一句我最喜歡的是
Its cruel, its tough, its business.....
第二句最中肯的是
錢不是萬能, 但是沒有錢就萬萬不能.....
You got to know both of them!!!~~~

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推 chia1985:謝謝^^
→ chia1985:請問yard跟mile的比例是要自己記嗎？
→ giyoshi:我忘了  我沒有記....lol  只是剛剛查的...
→ giyoshi:因為我覺得這種題目其實不難 但是解不出答案 我都認為
→ giyoshi:是題目的問題...我指的是數學部份...是就是 不是就不是
→ giyoshi:我認為我的解法對 沒有問題 我就去質疑題目 lol