请教几道PS

joywzy

5. At a certain diner, a hamburger and coleslaw cost $3.59, and a hamburger and french fries cost $4.40. If french fries cost twice as much as coleslaw, how much do french fries cost?
(A) $0.30
(B) $0.45
(C) $0.60
(D) $0.75
(E) $0.90

Ans: E
H+C=3.59, H+F=4.40, F=2C => F=1.62

20. Forty percent of the rats included in an experiment were male rats. If some of the rats died during the experiment and 30 percent of the rats that died were male rats, what was the ratio of the death rate among the male rats to the death rate among the female rats?
(A)  9/14        (B)  3/4        (C)  9/11
(D) 6/7         (E)  7/8

Ans: A


Month        Average Priceper Dozen
April  May June        $1.26$1.20$1.08
19. The table above shows the average (arithmetic mean) price per dozen of the large grade A eggs sold in a certain store during three successive months. If   as many dozen were sold in April as in May, and twice as many were sold in June as in April, what was the average price per dozen of the eggs sold over the three-month period?
(A) $1.08
(B) $1.10
(C) $1.14
(D) $1.16
(E) $1.18

Ans
(2/3)A=M, 2J=A, (1.26*A+ 1.2*M+1.08*J)/(A+M+J)=2.6/ 2.17=1.19

16. A family made a down payment of $75 and borrowed the balance on a set of encyclopedias that cost $400. The balance with interest was paid in 23 monthly payments of $16 each and a final payment of $9. The amount of interest paid was what percent of the amount borrowed?
(A) 6%
(B) 12%
(C) 14%
(D) 16%
(E) 20%

Ans; D
(75+23*16+9-400)/400=52/400=13%

11. A man who died left an estate valued at $111,000. His will stipulated that his estate was to be distributed so that each of his three children received from the estate and his previous gifts, combined, the same total amount. If he had previously given his oldest child $15,000, his middle child $10,000, and his youngest $2,000, how much did the youngest child receive from the estate?
(A) $50,000
(B) $48,000
(C) $46,000
(D) $44,000
(E) $39,000
Ans;D

3. Of the 1,000 students who entered College X as freshmen in September 1979,112 did not graduate in May 1983. If 962 students graduated in May 1983, how many of the graduates did not enter College X as freshmen in September 1979?

(A) 38                        (B) 74                (C) 112
(D) 150                (E) 188

Ans; B


Thank u !

[此贴子已经被作者于2003-2-13 14:38:24编辑过]

卧室春竹

从后向前说吧！~

1 1979年是一个春天..1000个同学进入了COLLEGE X 但是1983年 112个同学由于不好好学习没毕业.. 但是整个1983年毕业的学生是962

如果答案是B 那么做法就是 962-（1000-112） 但是 我有个疑问 这样的解法基于一个假设啊！ 就是1979年没进入COLLEGE X 的同学都毕业了。。

2 一个老同志死后要把家产均分给3个儿子.. 家产包括固定资产 还有原来给予3个儿子的各种东东

那么先算出来平均值.. (15000+10000+2000+111000)/3
然后再减去小儿子已经有的 2000  答案就是D

3 这个题 好像那儿做过！OG？ 分母我记得好像是除以325 不是400 开始等于花75块钱借了400 也就等于借了325？

4 一共N老鼠 40%男老鼠 60%母耗子 试验中死了X个
那么X*30%/N*40%再除以X*70%/N*60%

5 您J和A的关系弄错了 J/A=2

6 不懂 我也那么算得...

joywzy

19, twice as many were sold in June as in April=> J/A=2 ? 还是2J=A?

3. Of the 1,000 students who entered College X as freshmen in September 1979,112 did not graduate in May 1983. If 962 students graduated in May 1983, how many of the graduates did not enter College X as freshmen in September 1979?

(A) 38   (B) 74  (C) 112
(D) 150  (E) 188

Ans; B

能否再讲讲,我还是不明白.

5. At a certain diner, a hamburger and coleslaw cost $3.59, and a hamburger and french fries cost $4.40. If french fries cost twice as much as coleslaw, how much do french fries cost?
(A) $0.30
(B) $0.45
(C) $0.60
(D) $0.75
(E) $0.90

Ans: E
H+C=3.59, H+F=4.40, F=2C => F=1.62
这题我算了多遍,都是这个答案,不知哪里出了问题?

其它题目,已经理解,非常感谢!

tongxun

J/A=2

3. Of the 1,000 students who entered College X as freshmen in September 1979,112 did not graduate in May 1983. If 962 students graduated in May 1983, how many of the graduates did not enter College X as freshmen in September 1979?

(A) 38 (B) 74 (C) 112
(D) 150 (E) 188
----------------------------
1000人进来，112人完了，也就是说1979年入学的学生中，只有888人在毕业典礼上，拿了毕业证书。
但1983年毕业证书发了962个，也就是说有962-888=74人，不是在1979年入学的。（可能是1978年留级的，或1980年跳级的）

5、10倍还差不多。2倍就做不出来了。没办法。

joywzy

谢谢tongxun,第3题我明白了。

第5题到底怎么回事？