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#41726 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-09 18:09:38
#41727 Re: Jokes » www.funcyber.com/good-free-jokes : joke site » 2005-10-09 18:00:19
The proper link is
www.funcyber.com/good-fun-jokes/.
Click here
I haven't seen the contents on the website yet, I have just provided the link.
#41728 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-09 16:48:15
Problem # k + 26
There are 2 brothers among a group of 10 persons. In how many ways can the group be arranged around a circle so that there is exactly one person between the two brothers?
#41729 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-09 16:38:49
You are right Mathsy. The solution to the problem given was 81.5, which is certainly incorrect! I would solve the problem exactly the way you did
(I thought of the method of solving at the time of posting, but didn't actually solve it!)
#41730 Re: Introductions » Hi » 2005-10-09 16:32:59
I forgot to mention...I think Kylekatarn is from Portugal too 
#41731 Re: Help Me ! » Perfect Square Proof » 2005-10-09 16:31:22
A simple proof I can think of is
(a+b+c)²=a² + b² + c² + 2ab + 2bc + 2ac
When n=1 in your case,
a=10000, b=200, c=1
The resultant is 100000000 + 40000 + 1 + 4000000 + 400 + 20000 = 104060401.
This will continue as n increases.
For example, for n=2,
a=1000000, b=2000, c=1.
The resultant would be 1000000000000 + 4000000 + 1 + 4000000000 + 4000 + 2000000 = 1004006004001.
It can be seen that the other digits are not affected because of the number of zeros in a and b.
Hence, for any value of n, the resultant is a perfect square.
q.e.d
#41732 Re: Introductions » Hi » 2005-10-08 17:40:20
Hi frol....
I have a special place for Portugal in my heart, because I spent most of my childhood in Goa, India, earlier a colony of Portugal.
Here are some pictures of Goa....
#41733 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-07 23:19:39
Problem # k + 25
Three mathematics classes: X, Y, and Z, take an algebra test.
The average score in class X is 83.
The average score in class Y is 76.
The average score in class Z is 85.
The average score of all students in classes X and Y together is 79.
The average score of all students in classes Y and Z together is 81.
What is the average of all the three classes?
#41734 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-06 21:40:24
You are right, Mathsy!
#41735 Re: Help Me ! » Math Study Tips... » 2005-10-06 20:50:22
Understand the logic. Learn the techniques. Remember the formulae. Practice methods of proving. Most important, hone your calculation skills and never forget the fundamental concepts.
#41736 Re: Help Me ! » help plz » 2005-10-06 20:39:22
Yes, very much British
#41737 Re: Help Me ! » help plz » 2005-10-06 16:13:35
In India,
y = mx + c
where c is the y intercept and -x/y is the slope (or gradient),
when written as y - mx - c = 0
#41738 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-06 16:03:32
Problem # k + 24
A cube is made by cutting off the excess portions of a sphere of radius r. What is the volume of the biggest cube that can be formed?
#41739 Jokes » Tips to improve your writing » 2005-10-06 00:06:21
- Jai Ganesh
- Replies: 13
1. Avoid alliteration. Always.
2. Never use a long word when a diminutive one will do.
3. Employ the vernacular.
4. Eschew ampersands & abbreviations, etc.
5. Parenthetical remarks (however relevant) are unnecessary.
6. Remember to never split an infinitive.
7. Contractions aren't necessary.
8. Foreign words and phrases are not apropos.
9. One should never generalize.
10. Eliminate quotations. As Ralph Waldo Emerson said, "I hate quotations. Tell me what you know."
11. Comparisons are as bad as cliches.
12. Don't be redundant; don't use more words than necessary; it's highly superfluous.
13. Be more or less specific.
14. Understatement is always best.
15. One-word sentences? Eliminate.
16. Analogies in writing are like feathers on a snake.
17. The passive voice is to be avoided.
18. Go around the barn at high noon to avoid colloquialisms.
19. Even if a mixed metaphor sings, it should be derailed.
20. Who needs rhetorical questions?
21. Exaggeration is a billion times worse than understatement.
22. Don't never use a double negation.
23. capitalize every sentence and remember always end it with point
24. Do not put statements in the negative form.
25. Verbs have to agree with their subjects.
26. Proofread carefully to see if you words out.
27. If you reread your work, you can find on rereading a great deal of repetition can be avoided by rereading and editing.
28. A writer must not shift your point of view.
29. And don't start a sentence with a conjunction. (Remember, too, a preposition is a terrible word to end a sentence with.)
30. Don't overuse exclamation marks!!
31. Place pronouns as close as possible, especially in long sentences, as of 10 or more words, to the irantecedents.
32. Writing carefully, dangling participles must be avoided.
33. If any word is improper at the end of a sentence, a linking verb is.
34. Take the bull by the hand and avoid mixing metaphors.
35. Avoid trendy locutions that sound flaky.
36. Everyone should be careful to use a singular pronoun with singular nouns in their writing.
37. Always pick on the correct idiom.
38. The adverb always follows the verb.
39. Last but not least, avoid cliches like the plague; They're old hat; seek viable alternatives.
#41740 Re: Dark Discussions at Cafe Infinity » Wink Murder 4 » 2005-10-04 23:15:39
Playing
justlookingforthemoment
MathsIsFun
Mathsyperson
Zach
insomnia
Ganesh may be added to the list
#41741 Re: Guestbook » tanks » 2005-10-04 23:13:37
#41742 Re: Help Me ! » combinatorics in playing cards - 52 caard standard deck » 2005-10-04 23:08:43
I think the required probability is
(32 x 28 x 24)/(52 x 51 x 50) assuming the raminaing two cards can be either paired or unpaired, greater or lesser than nine.
#41743 Re: Help Me ! » Algebra in Standard form.. » 2005-10-04 22:34:35
The slope of 4x-2y+7=0 is 2.
Therefore, the perpendicular to this line has a slope -1/2.
The y-intercept 2x+3y-10=0
is 10/3.
Therefore, the line passes through (0, 10/3)
The equation of the line would be
y - 10/3 = -1/2(x - 0) = -x/2
2y - 20/3 = -x
x + 2y - 20/3 = 0
3x + 6y - 20 = 0 is the required equation.
#41744 Re: Help Me ! » Need help in this problem... » 2005-10-04 16:57:53
Given two points, the equation of the line joining the points is
(y-y1)/(y2-y1) = (x-x1)/(x2-x1)
Substituting y1 = 5, y2 = -1, x1 = 3 and x2 = -3, the equation of the line is
x-y+2 = 0,
The slope of this line m=(y2-y1)/(x2-x1), i.e., m = 1.
The slope of a line perpendicular to this line would be -1
(Because, if two lines are perpendicular, the product of their slopes is -1).
The midpoint of U(3,5) and V(-3, -1) is given by
[(x1+x2)/2, (y1+y2)/2]
Therefore, the midpoint of the line UV is
(0,2).
The equation of a line of given slope passing through a given point is
(y-y1) = m(x-x1)
We know, m=-1 for the perpendicular line.
Therefore, the equation of the perpendicular bisector is
(y-2) = -1(x-0)
or
x+y-2 = 0
Substitute the x and y coordinates of point W(2,-1) in this equation.
We see that it does not satisfy the equation.
Therefore, the point does not lie on the perpendicular bisector.
#41745 Re: Help Me ! » hel[p me with this problem » 2005-10-04 16:04:36
196
---- = 14
F
Therefore,
196
---- = F
14
When 196 is divided by 14, we get 14.
Therefore,
F = 14
#41746 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-30 18:27:51
Mathsy, all your solutions are correct! You had understood problem # k + 16 rightly!
#41747 Re: Dark Discussions at Cafe Infinity » Wink Murder 3 » 2005-09-30 18:14:17
Me too playing
#41748 Re: Help Me ! » Orders of Operation Help » 2005-09-30 18:04:27
Step 1 : Do Operations within the Parentheses
3 - (6 + 8) x 3 = 3 - 14 x 3 = 3 - 42 = -39
The first operation to be done is always the one within the Parantheses.
Step 2 : Do Operations with Powers and Roots
3 + 2^5 = 3 + 32 = 35 (Here ^ represents powers)
3 + √ 16 = 3 ± 4 = 7 or -1.
Step 3 : Do all multiplication and division operations from left to right
Step 4 : Do all addition and subtraction operations from left to right
50 ÷ 10 ÷ 2 = (50 ÷ 10 ) ÷ 2 = 5 ÷ 2 = 2.5
If it is done from the other direction, you get a different (and wrong) answer.
#41749 Re: This is Cool » pi: the phantom of mathematics » 2005-09-26 16:01:36
Euler's equation!
This is because
(Cosθ + iSinθ)^n = Cos(nθ) + iSin(nθ)...DeMoivre's equation
and Cosθ + iSinθ=e^(iθ)
When θ=Pi (radians)
e^(i*pi) = Cos(pi) + iSin(pi)
We known Cos(pi)=-1 and Sin(pi)=0,
Therefore,
e^(i*pi)=-1
or
e^(i*pi) + 1 = 0
#41750 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-19 16:07:22
Problem # k + 23
A Pythagorean triple is a set of three numbers (a,b,c) such that
a² + b² = c². For example, (3,4,5).
Prove that three prime numbers cannot form a Pthagorean triple.