[原创]2006年11月MathJJ讨论第一篇-完(1-99)

kastiny

    

前面有人讨论过了

    

330既然是连续正整数乘积的"因数"

    

9*10*11=990就是330的倍数了

    

所以根本不需要到11!

    

而且题目也没规定连续正整数一定是要从1开始

    

欢迎大家讨论　我也想知道最後的正确答案

[此贴子已经被作者于2006-11-8 17:56:52编辑过]

rxf9703

感觉几个有问题的题目，有些是不会，有些题目也理解不了，大家帮看看：

71.f[x] is defined to the closest number equal or less x, f[y]=2, f[x/3]=?

 

answer 0

 

72.(this one I absolute don't remember the details, sorry) JiHe problem - number of P is twice as M, MP together is 1/2 of M only, total number of MP together is 5000, ask P only.

 

Answer 10,000 - reasoning M-only has 1 unit, MP together 2 units, and P only 4 units (because (4+2)=2x(1+2)

 

74. Asking the total distance of a triangle, whose 3 points are (-4, 3) (3,4) and (-1,1) on the XY-plane. It also said something about the points were on a lake, come with a drawing too.

 

Answer 17.  (-4, 3) to (3,4) is 50^2 the other two are 5 each. The total is estimated.

 

79.There is one more I remember, but couldn't draw - 4 lines intersect each other forming a "#" not necessarily //.  4 corner w, x, y and z.  Ask x+z=?  1) w=95 2)z=125 Answer is D for sure

rxf9703

以下是引用kastiny在2006-11-6 18:01:00的发言：

这题我觉得应该是3喔

前面有人讨论过了

330既然是连续正整数乘积的"因数"

9*10*11=990就是330的倍数了

所以根本不需要到11!

而且题目也没规定连续正整数一定是要从1开始

欢迎大家讨论　我也想知道最後的正确答案

  

MM没看到题目中的"first "吧？ 呵呵

xfysn

BruceChiang,你说的X=3或=4恰好说明X<=4 从而得到一个"X不是>=4"的答案,这就是对题目的回答...不知道对不对...

[此贴子已经被作者于2006-11-6 19:15:19编辑过]

kastiny

真是不好意思
念书念到眼花了
谢谢你的指正~~

xfysn

63.      k is an integer, what is the remainder of (k^2)/8?

(1)    k divided by 2, the remainder is 1

(2)    k divided by 3, the remainder is 2

解：A

那K=3时余数是几呢?

[此贴子已经被作者于2006-11-6 19:38:07编辑过]

kastiny

to rxf9703

感觉几个有问题的题目，有些是不会，有些题目也理解不了，大家帮看看：

71.f[x] is defined to the closest number equal or less x, f[y]=2, f[x/3]=?

answer 0

这一题我认为是条件或答案有误　我想应该是f(x)=2　然後判定x近似於2

所以f(x/3)=f(2/3)= "closet interger"=1  ---->更正为0 因为题目说要 the closest integer equal or less than x我眼花没看到

因为x至少要大於1.5才能使f(x)=2

大於1.5的数除3无论如何最近的整属应该都是1才对

72.(this
one I absolute don't remember the details, sorry) JiHe problem - number
of P is twice as M, MP together is 1/2 of M only, total number of MP
together is 5000, ask P only.

这题我也不了解　大家讨论吧

 

Answer 10,000 - reasoning M-only has 1 unit, MP together 2 units, and P only 4 units (because (4+2)=2x(1+2)

 

74.
Asking the total distance of a triangle, whose 3 points are (-4, 3)
(3,4) and (-1,1) on the XY-plane. It also said something about the
points were on a lake, come with a drawing too. 

 

Answer 17.  (-4, 3) to (3,4) is 50^2 the other two are 5 each. The total is estimated.

我想是问三角形周长＜作者可能也算错了　另外两边不是each5 只有一个是5

    

答案should be √50+√13+5近似於15.6　

 

79.There is one more I remember, but couldn't draw - 4 lines intersect each other forming a "#" not necessarily //.  4 corner w, x, y and z.  Ask x+z=?  1) w=95 2)z=125 Answer is D for sure

这题应该是说四条线交成一个井字
可是彼此不必然平行
然後ＷＸＹＺ分别是这个封闭的四边行内角
但是没有图我还是解不出来的　看有没有好心的NN会来补充机经了^^

[此贴子已经被作者于2006-11-7 21:12:15编辑过]

kastiny

to rxf9703

感觉几个有问题的题目，有些是不会，有些题目也理解不了，大家帮看看：

71.f[x] is defined to the closest number equal or less x, f[y]=2, f[x/3]=?

answer 0

这一题我认为是条件或答案有误　我想应该是f(x)=2　然後判定x近似於2

所以f(x/3)=f(2/3)= "closet interger"=1

因为x至少要大於1.5才能使f(x)=2

大於1.5的数除3无论如何最近的整属应该都是1才对

72.(this
one I absolute don't remember the details, sorry) JiHe problem - number
of P is twice as M, MP together is 1/2 of M only, total number of MP
together is 5000, ask P only.

这题我也不了解　大家讨论吧

 

Answer 10,000 - reasoning M-only has 1 unit, MP together 2 units, and P only 4 units (because (4+2)=2x(1+2)

 

74.
Asking the total distance of a triangle, whose 3 points are (-4, 3)
(3,4) and (-1,1) on the XY-plane. It also said something about the
points were on a lake, come with a drawing too. 

 

Answer 17.  (-4, 3) to (3,4) is 50^2 the other two are 5 each. The total is estimated.

我想是问三角形周长＜作者可能也算错了　另外两边不是each5 只有一个是5

    

答案should be √50+√13+5近似於15.6　

 

79.There is one more I remember, but couldn't draw - 4 lines intersect each other forming a "#" not necessarily //.  4 corner w, x, y and z.  Ask x+z=?  1) w=95 2)z=125 Answer is D for sure

这题应该是说四条线交成一个井字
可是彼此不必然平行
然後ＷＸＹＺ分别是这个封闭的四边行内角
但是没有图我还是解不出来的　看有没有好心的NN会来补充机经了^^

xfysn

楼上,这几道题同感,都想放弃了...

uniqueben

關於38題，我的想法是：

條件1：median是4，由於驗證結果X是<=4，所以X不是>=4

這樣子的話，條件1應該就算是可以成立了.....吧