507. D .4
509. "if the sign is 3 centimeters long" - what does this mean?
1.a+2r=3, a=2r--> r=3/4, a=3/2 then Volum=(3/2)^3+4*3/2*Pai*(3/4)^2/2
=3.375+1.6875Pai
2. ...
Anyway, the question I can't understand. In addition," 3 centimeter",whcih I guess should be 3 meter.
510: C
541: E
Can u check our answer/ thanks!作者: 劲松 时间: 2002-9-15 12:48 标题: 数学问题
以下数学问题出自新东方补充材料
我解出不同答案，但实在想不明白。费费的答案稍后公布，大家帮忙解解看
507
Three stacks containing equal numbers of chips are to be made from 9 red chips, 7 blue chips, and 5 green chips. If all of thes chips are used and each stack contains at least 1 chip of each color, what is the maximum number of red chips in any one stack?
A.7 B.6 C.5 D.4 E.3
509
The figure（就是一个正方形，每边外面加一个半圆的图形，看上去像个四瓣的花） shows the shape of a sign to be placed in front of a flower store. The sign has a semicirle on each side of the square, if the sign is 3 centimeters thick and if each side of the square is 50 centimeters long, what is the volume, in cubic centimenters. of the sign?
A.1250pi+2500 B.3750pi C.3750pi+7500 D.5000pi+7500 E.11250pi
510
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
541
A computer is programmed to generate a list of multiples of prime numbers 2, 3, and 5, as shown below:
-------------------------------------
Program 1-List multiples of 2
Program 2-List multiples of 3
Program 3-List multiples of 5
-------------------------------------
How many integers less than 100 will appear on all of the lists of programs produced above?
A.None B.1 C.3 D.5 E.An infinite number of integers
[此贴子已经被作者于2002-9-15 12:48:49编辑过]
作者: 劲松 时间: 2002-9-15 12:52
对不起，昨天的509问题打掉了一段话，今天补上了
答案是CCEE作者: cook 时间: 2002-9-15 13:54
507. sorry should be 5. According to context, 7 for each since equal number and total number of 21, First, 1 each color for each group.then go blue color, green , ans the last to distribute red.
R R R 9-3=6
B B B 7-3=4
G G G 5-3=2
4B 2G+2R (6-2)R
Total
7 7 7
So, the number of maximum red = ( 6-2)+1=5
509. Method: 50^2*3 + Pai*1/2*(50/2)^2*3*4 = 3750pi+7500 --> C
510. Are u sure? My way goes like this:
(2) x, 2x, 3*2x if 3*2x=2 --> x=1/3
Can u check it again? thanks!作者: 劲松 时间: 2002-9-15 18:06
