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#43776 Re: Dark Discussions at Cafe Infinity » Wink Murder 2 » 2005-07-15 22:57:15
I am jumping in! 
#43777 Re: This is Cool » Solve this! » 2005-07-15 22:46:25
You are correct, tt! 
#43778 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-07-15 22:43:33
Thats right!
This is how it is solved.
40 litres of milk and water contain 10% water.
Therefore, the milk content is 36 litres and water is 4 litres.
Lets assume x litres of water are added to make water 20%.
The ratio of water to the total becomes
4+x/40+x
this is equal to 20/100 or 1/5.
4+x/40+x = 1/5,
5(4+x) = 40+x
20+5x = 40+x
4x=20
x=5 litres
#43779 Re: This is Cool » "A Maths Dictionary for Kids" » 2005-07-14 23:18:10
Don't hate Mathematics, Zoe! Mathematics is fun, believe me! 
#43780 Re: Dark Discussions at Cafe Infinity » Wink Murder » 2005-07-14 23:15:58
I wonder if ganesh would like to play?
I am too old...I am more than 10,000 days old! 
#43781 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-07-14 23:02:55
That is close to a 1,000 gallons!
#43782 Re: Jokes » Limericks » 2005-07-14 19:52:23
who looked much like a lizard
#43783 Re: Puzzles and Games » rabbit farm » 2005-07-14 19:41:49
You mean 144? My friend says it is ___!
#43784 Re: Maths Teaching Resources » Welcome » 2005-07-14 18:59:54
I can live on 100 litres of coke a month, without food 
#43785 Re: Help Me ! » I need your help » 2005-07-14 17:57:42
I discovered that 2^20 ends in 76.
Thereafter, any number of the form 2^20n ends in 76.
Similarly, any number of the form 2^100n ends in 376.
Next, I had to know the last few digits of 2^500 and 2^2500.
When I learnt that they are 9376 and 09376, I was excited.
Because, any number of the form 2^500n would then have to end in 9376
and every 2^2500n would have to end in 09376.
This is what Rora was talking about. You are too young to understand this, Maxine. This is about higher powers of the number 2.
#43786 Re: Puzzles and Games » rabbit farm » 2005-07-14 17:47:58
This is much more complicated than what I thought!
#43787 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-07-14 17:10:52
Outstanding! You are really supersmart!
Try this one....But don't post your reply immediately.
Let others too try.
(2) A mixture of 40 liters of milk and water contains 10% water. How much water must be added to make water 20% in the new mixture?
#43788 Re: Guestbook » guinea-pigs » 2005-07-14 17:00:41
I had one which lived with me for three years. I just love them, they are so cute
#43789 Re: Help Me ! » Hi » 2005-07-14 16:46:57
Hey you guys are pretty smart
Thanks, Jenilia. Visit the 'Games and Puzzles' topic regulalry. I shall post mathematical problems and their solutions which could be of some help to you, for the Olympiad.:)
#43790 Jai Ganesh's Puzzles » Problems and Solutions » 2005-07-14 16:43:22
- Jai Ganesh
- Replies: 468
In this topic, I shall give a problem and give the (proper mathematical) solution after a week.:D
The first one:-
The population of a town increases by 5% annually. If its population in 1995 was 138915, what was it in 1992?
#43791 Re: Puzzles and Games » Work done in time! » 2005-07-14 16:39:02
Excellent! You are correct! Tell us how you did it!
#43792 Re: This is Cool » Mathematic complexity » 2005-07-14 16:33:50
If Quasimodo had stumbled upon hidden treasure, then he may have discovered
#43793 Puzzles and Games » Work done in time! » 2005-07-13 23:15:48
- Jai Ganesh
- Replies: 5
A contractor agrees to complete a work in 100 days. He engaged 140 men for the job and after doing the work for 60 days, he came to know that only half the work was completed. How many more men should he hire to finish the work in the agreed time?
#43794 This is Cool » Which of the two is greater? » 2005-07-13 21:39:52
- Jai Ganesh
- Replies: 6
When there are two numbers x and y, such that both x,y ≥1,
does it follow that y^x is always greater than x^y if x is greater than y?
No.
This is true only if y is greater than a certain CRITICAL Value.
Many years back, I tried to find this critical value of y for certain values of x.
Value of x Approximate value of y
10 1.3712886
100 1.04955
1000 1.0069805
10,000 1.000922309
100,000 1.00011514925
1,000,000 1.0000138158
10,000,000 1.00000161283
100,000,000 1.0000001843
1,000,000,000 1.0000000208
Illustration:- y^100 can be greater than 100^y only if the value of y ≥1.04955
#43795 Re: Puzzles and Games » The light switch » 2005-07-13 21:17:21
23+18+12+22 is already greater than 30! So, it should be 'people' as pointed out by Mathsy!:)
#43796 Re: Help Me ! » Hi » 2005-07-13 21:10:05
That's because, in all the odd numbers up to 99,
there are 10 numbers ending in '5'.
5, 15, 25, 35, 45, 55, 65, 75, 85, and 95.
And, when an odd number is multiplied by a
number ending in '5', the resultant always ends in '5':)
#43797 Re: Puzzles and Games » The light switch » 2005-07-13 20:52:58
1 + 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256 + .............1/ ∞ = 2
I cannot think beyond that.
#43798 Re: Help Me ! » Hi » 2005-07-13 20:43:03
My best wishes to you, Jenilia.
You can post all your mathematical doubts here.
We'd try to help you.
#43799 Re: Help Me ! » I need your help » 2005-07-13 19:04:11
Is it also necessary to prove it for n=1 ?
First, the formula or equation is checked for values like 1,2,3 etc.Only if this test is pased, we asume it is true for an arbitrary number k. Thereafter, if it is proved true for k+1, it becomes a 'proof beyond doubt'.
#43800 Re: Jokes » Limericks » 2005-07-13 17:17:15
There once was a boy from Montreal
Who loved to play basketball
For a team he tried out
But if he made it, I doubt
For you see, he was three feet tall!:D