数学题[求助]

lnlynn

好多题，有劳大家了，谢谢
补充材料
541 A computer is programmed to generate a list of multiples of prime numbers 2,3 and 5,as shown below:
Program 1-list multiple of 2
2- 3
3- 5
how many integers less than 100 will appear on all of the lists of programs produced above?

534 DS if the number of square units in the area of a circle is A and the number of linear units in the circumference is C,what is the radius of the circle? （不明白题意）
(1) A/C=3/2
(2) A>C+3

510 DS what is the 1st  term in sequence S?
(1) the 3rd  term in S is 2
(2) the 2nd  term in S is twice the 1st ,and the 3rd term is three times the 2nd

498 a merchant sells an item at a 20 percent discount,but still makes a gross profit of 20 percent of the cost .what percent of the cost would the gross profit on the item have been if it had been sold without the discount?

491 of the following ,which best approximates(0.1667)(0.8333)(0.3333)/(0.2222)(0.6667)(0.1250)
answers: 2.00   2.40   2.43   2.50   3.43

492.two searchlights S1 and S2 are located 10,000 feet apart,each covers and area of radius 10,000 feet, and each is located 8,000 feet from the railroad track.To the nearest 1,000 feet,what is the total length x of track spanned by the seachlights?

482.what is the least number of digits (including repetitions)needed to express 10^100 in decimal notation? （不明白题意）
[em21][em20][em21][em07][em07][em28]

andrewcan

491: 2.5   change the decimals to fractions: ie. 0.1667= 1/6, 0.8333 = 1/1.2....

492: 24,000, to draw a picture, it will be much clearer. you will find out the answer is 4 X 6,000 ---------> 24,000
482: I think "number of digits" mean: 3 in 10^2( =100); 5 in 10^4( =10000)
     so 10^100  ----101.

nan

492)
my answer is 10,000+2*6,000=22,000

nan

489)
i don't know that wrong with me but my answer is 50%

lnlynn

489）我也是50%，但答案是40%，答案错了？
492）按的方法，答案同nan
andrewcan对482的讲解明白，但题中为何会问the least number?
andrewcan可否告诉我有何简便方法将小数变分数，比如我就看不出0.8333 = 1/1.2....

andrewcan

sorry the key to 492 should be 22,000.

How to figur out 0.8333= 1/1.2 ?   Use a calculator !  ----kidding

try to translate 0.83333 to 0.8+0.03333 = 4/5 + 1/30 = 6/5 ----> 1.2

well, memorising some basic ones ( 0.3333...1/3; 0.125 1/8; 0.625 1/1.6....) is surely helpful.

[em11]

[此贴子已经被作者于2002-11-10 1:54:31编辑过]

三十画生

541）29
534）A
不知以上答案是否正确，不敢误导大家。
489）我也认为答案有误。
请问lnlynn，补充材料是什么复习材料？

lnlynn

andrewcan好耐心哦，谢谢你！
‘三十画生’兄弟，541的答案是a denifite number of integers,但我理解题意是求100以内有多少个2，3，5的公倍数，因为只有它们的公倍数才会出现在三个栏里，应有三个30，60，90。不知答案为何说不确定？
534是选A，请赐教，（可以简单翻译一下吗）
补充材料是我8月在新东方上班时发的，大概以前的同学发的是分册，我们只有发OG和补充材料（包括OG不全的各部分题），作文书也是红皮的，不是绿皮的，新东方门口小贩有卖。

三十画生

lnlynn,那我就大胆说了：）
534）一定是你没看懂题意，简单的会让你晕倒。题意是：如果一个圆的面积是A个面积单位，周长是C个长度单位，那么圆的半径是多少？而A和C并不是我们认为的常量，而是未知量，所以答案a中A/C＝3/2＝r

lnlynn

三十画生，你的直白就是对我的帮助啊，谢谢！