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#41426 Re: Jokes » joke! » 2005-07-06 17:08:21

Let robbis babe have this one,
I shall change my avatar.

#41427 Jokes » Human Body and Numbers » 2005-07-05 22:58:36

Jai Ganesh
Replies: 5

1. Our heart beats around 100,000 times every day.

2. Our blood is on a 60,000-mile journey.

3. Our eyes can distinguish up to one million color surfaces and take in more information than the largest telescope known to man.

4. Our lungs inhale over two million liters of air every day, without even thinking. They are large enough to cover a tennis court.

5. Our hearing is so sensitive it can distinguish between hundreds of thousands of different sounds.

6. Our sense of touch is more refined than any device ever created.

7. Our brain is more complex than the most powerful computer and has over 100 billion nerve cells.

8. We give birth to 100 billion red cells every day.

9. When we touch something, we send a message to our brain at 124 mph.

10. We have over 600 muscles.

11. We exercise at least 30 muscles when we smile.

12. We are about 70 percent water.

13. We make one liter of saliva a day.

14. Our nose is our personal air-conditioning system: it warms cold air, cools hot air and filters impurities.

15. In one square inch of our hand we have nine feet of blood vessels, 600 pain sensors, 9000 nerve endings, 36 heat sensors and 75 pressure sensors.

#41428 Re: Jokes » joke! » 2005-07-05 21:52:10

Robbies,
You change your avatar or I change mine..
The choice is yours!
Do reply.

#41429 Re: Introductions » All Hail the Super Member!!! » 2005-07-05 21:14:37

Well done, Mr T; Keep up the good work!

#41430 Re: Help Me ! » What is da Pythagoros theorem » 2005-07-05 21:11:25

Yes, 2(n)+1 and 2(2n+1)+1 are both odd numbers!

#41431 Re: Help Me ! » What is da Pythagoros theorem » 2005-07-05 17:23:50

The three values of the sides of a right angled triangle are also called a Pythagorean Triple.
A Pythagorean triple is a set of three whole numbers , such that one number squared added to another number squared equals the third number squared. Euclid could prove that there are an infinite number of such Pythagorean triples.

Euclid's proof begins with the observation that the difference between successive square numbers is always an odd number.
4 - 1 = 3,  9 - 4 = 5,  16 - 9 = 7, 25 - 16 = 9, 36 - 25 = 11, 49 - 36 = 13 etc.

#41432 Dark Discussions at Cafe Infinity » Mathematical proof » 2005-07-05 16:46:49

Jai Ganesh
Replies: 8

Mathematicians are notorious for being sticklers when it comes to requiring absolute proof before accepting any statement. Their reputation is clearly expressed in a story told by Ian Stewart in 'Concepts of Modern Mathematics':-


An astronomer, a physicist, and a mathematician (it is said) were holidaying in Scotland. Glancing from a train window, they observed a black sheep in the middle of a field.
'How interesting' observed the astronomer, 'all Scottish sheep are black!' To which the
physicist responded, 'No, no! Some Scottish sheep are black!' The mathematician gazed heavenward in supplication, and then intoned, 'In Scotland there exists at least one field, containing at least one sheep, at least one side of which is black.'


Taken from 'Fermat's Last Theorem' by Simon Singh

#41433 Re: Help Me ! » Any Guesses????? » 2005-07-05 16:23:34

Mathsy is right! This is a puzzle and crept into 'Help me' by mistake.
Anyway, I shall give the solution.
One dice is marked 0,1,2,3,4,5.
The other is marked 0,1,2,7,8,9.
Don't ask me how you get 6!

#41434 Re: This is Cool » Remembering sin and cos values » 2005-07-04 23:12:09

Similalry, how do you tell whether sin or cos or tan of an angle is positive or negative?
Just remember the mnemonic 'All Silver Tea Cups'.
In the first quadrant, i.e. 0 to 90 degrees, All the angles are positive.
In the second quadrant, 90-180 degrees, only Sine is positive (remember S of Silver!)
In the third quadrant, 180-270 degrees, only Tan is positive. (remember T for Tea)
In the fourth quadrant, i.e. 270 to 360 degrees, only Cos is positive. (C for Cups)

#41435 Re: Help Me ! » Any Guesses????? » 2005-07-04 22:55:24

Nevermind getting a silly combination like 38,
but how would you display, say 22, 23, 24 or 25???

#41436 Re: Help Me ! » Any Guesses????? » 2005-07-04 22:01:56

I clarify...
On each of the six sides of the two dices, any six numbers
0, 1, 2, 3, 4, 5, 6, 7, 8 or 9
are marked. It could be any of these ten numbers.
The condition is that it should be possible to display all the dates from 01 to 31.
Further, dates with single digits should be displayed as 01, 02, 03 etc.
What markings would make this possible, thats the question.
There's only one solution to this problem.

#41437 Re: Help Me ! » Any Guesses????? » 2005-07-04 21:25:45

Two dices are marked with numbers from zero to nine on each face.
The two dices are meant to display all the dates in a month from 01 to 31.
Remember, single digit dates would have to be shown as 01, 02, 03 etc.
That is, one dice should show zero and the other 1 or 2 or 3 and so on.
The two dices can be interchanged i.e. placed in any order.
What would be the numbers written on the six faces of the two dices???

#41438 Re: Puzzles and Games » Crooked Clocks » 2005-07-04 20:26:16

Clue No.1 :- First, figure out what time the clocks were set

#41439 Re: This is Cool » What went wrong? » 2005-07-04 20:22:27

oh yes, we did....Maybe we started the same time, but you finished earlier.

#41440 Re: Help Me ! » I need your help » 2005-07-04 20:20:50

Squares should be sufficient. I'll do the remaining part, by checking for higher powers.
I am too not sure if this can be done much further, because there's a possibility it may end somewhere.

#41441 Re: This is Cool » What went wrong? » 2005-07-04 20:11:49

10 raised to the power 6 is 1,000,000.
We say Logarithm of 1,000,000 to the base 10 is 6.
if a^b=c
(read as a raised to the power b equals c)
then, Logarithm of c to the base a is b.
In short, we say log(to the base a)  c = b
Common logarithm uses the base 10,
Natural logarithm uses the base 'e'.
Logarithms, discovered by John Napier, makes calculations far easier.
Multiplying two numbers is simply adding their logarithms (to the same base).
For example, logarithm value (to base 10) of a few numbers are given.
log 2 = 0.30103
log 3 = 0.47712
log 7 = 0.8451
log 10 = 1
and so on.

#41442 Re: Help Me ! » I need your help » 2005-07-04 20:04:41

No, Thank you, Administrator...
That was only for 'Im really bored'.
What I meant was that question was intended to be answered without use of computers.
Anyhow, what would be of help to me is.......
I discovered that the higher power of any number ending in
743740081787109376 would end in the same number.
If you can add a few more digits ahead of that???????

#41443 Re: Help Me ! » I need your help » 2005-07-04 17:00:29

You maybe right, I'm not too sure,
but I wanted that to be done without a computer.
And the last digit is 7.
Moreoever, I wanted only the last digit.
There's a pattern which makes it easy to tell.

Anyhow, than you, dear member, for first helping out with the
last 5 digits of 2^500 and 2^2500.

#41444 Re: This is Cool » What went wrong? » 2005-07-04 16:29:43

When I moved from step(2) to step(3),
I was taking logarithm of 1/2.
Logarithm of 1/2 is a negative number.
(For example, logarithm(base10) of 1/2 is -0.3010 approximately)
When an inequation is mutliplied by a negative number,
the inequality reverses direction.
Thats it!
eg. 5>2
But when this inequation is multiplied by -2,
-10<-4

#41445 Re: Help Me ! » I need your help » 2005-07-04 16:19:50

Higher powers of numbers ending in 0,1,5, and 6 end in themselves.
Of these numbers, I was most interested in 6 because numbers of the form 2^4n end in 6.
For that matter, the last digits of higher powers rotate in cycles of 4, thus, they can easily be known.
For example, try to figure out what the last digit of 23^611 would be. I shall help you with that if there are no answers.

#41446 Re: Help Me ! » This one's a sitter » 2005-07-04 16:14:27

You are right. But all numbers upto 20 only, not 22.

#41447 Re: Help Me ! » I need your help » 2005-07-03 23:04:39

At some point,
2 raised to the power of
4 x 5^n
would end
1787109376.
Thereafter, every higher power of that number would end
in 1787109376.
This is because any power of a
number having its last 10 digits as
1787109376
ends in 1787109376 !!!

#41448 Re: Help Me ! » I need your help » 2005-07-03 21:20:59

I really don't need to bother what the higher dgitis are.
The last 10 digits would do.
Thanks again, for the trouble taken and the time spent.

#41449 Puzzles and Games » Try this one! » 2005-07-03 21:05:11

Jai Ganesh
Replies: 6

I have 4 marked weights with me and they all add up to 40 kg.
With a pair of scales, I can distribute any weighment from 1 to 40 kg(Whole numbers).
What are the four weights????

#41450 Re: Help Me ! » I need your help » 2005-07-03 20:57:46

Thank you, Gentleman!
Yes, I just want to generate the output of
2^500, 2^2500 and 2^12500.
If possible, even 2^62500 and 2^312500
The last number of these would be about 100,000 digits.

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