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#976 Re: This is Cool » Barber's Paradox! » 2007-06-06 01:32:12

What if the barber did not have hair? What if the barber was a computer program which sent information to robots to cut client's hair?

#977 Re: Dark Discussions at Cafe Infinity » Basic Quantum Physics » 2007-06-06 00:15:32

When you are firing the photon at the screen, doesn't it matter in which direction you fire it? Or are you talking about the case where the photon is fired directly at the space between the two slits?

#978 Re: Help Me ! » Rectangle Measurements » 2007-06-06 00:10:11

How are FGC and BGC similar? Could you please provide a proof?

#979 Re: Dark Discussions at Cafe Infinity » Biology » 2007-06-05 20:13:18

Say you have a high concentration of oxygen inside a cellulose bag, and a lower concentration outside. The net movement will be from inside to outside, but some particles from outside will still by chance happen to come in (remember that particle movement is based on probability, brownian motion - there is a higher probability that something will go out than come in)

#980 Help Me ! » Rectangle Measurements » 2007-06-05 19:20:03

Identity
Replies: 4

This is a problem that I've had a bit of a headache over, find the length FG.
If possible, please only use similarity, congruency, pythagoras, and trigonometry, to do this, not coordinate geometry or anything too advanced. Thanks!

#981 Re: This is Cool » Infinity » 2007-06-05 00:41:32

Ok, why did u just copy a massive blob of text from Wikipedia?

#982 Re: Help Me ! » Questions » 2007-06-04 03:57:58

well too bad you missed that, but seems like you did very well big_smile overall! Sometimes I wonder if exams really test your true knowledge of maths, or your skills at sitting exams, because its easy for even the best mathematician to make mistakes in a panic.

#983 Re: Help Me ! » Comparing interest rates » 2007-06-04 03:41:20

Say if you were to analyse Ben and Simon's investments without regard to the 10 year period.
If I were to prove that Simon's is better than Ben's, would this be a good way of explaining it?
Since there is no intersection between the two graphs, we know that one investment is always greater than the other. Next, choose a test point, say x = 10, then we know that Simon's is better.

#984 Re: Introductions » sup » 2007-06-04 03:38:14

I'd say on a rare scale from 1 to 10 my name is about a 9, but I'm not tellin' u tongue

#985 Re: Jai Ganesh's Puzzles » 10 second questions » 2007-06-04 03:35:54

ganesh wrote:

171. The average of 5 quantities is 6. The average of 3 of them is 8. What is the average of the remaining two numbers?

Probably took about 15 seconds, need to work on mental arithmetic =_=

#986 Re: Help Me ! » Comparing interest rates » 2007-06-04 01:26:11

Sorry, it was a typo in the question big_smile! Anyway if this were in a test would you just graph the equations and draw the graph on the paper or solve with logs?

#987 Help Me ! » Comparing interest rates » 2007-06-03 22:53:20

Identity
Replies: 6

Three people invest 20000 for 10 years. Sam decides to invest in a 8% p.a simple interest account. Simon decides to invest in a 6% account, compounding monthly. Ben decides to invest in a 6.5% p.a compound interest account. Explain the benefits and disadvantages of each investment.

This right?



Now how do I explain advantages and disadvantages of each?

#989 Re: Help Me ! » Calculus: some problem with limits... » 2007-06-02 05:01:33

So there is no single algorithm for simplifying limits, but a whole bunch of different methods? Are there any limits that exist but cannot be solved?

#990 Re: Help Me ! » Proportionality » 2007-06-02 04:56:05

Daniel, you can use this site as a reference when using LateX
http://www.maths.tcd.ie/~dwilkins/LaTeXPrimer/

E.g

is \propto

#991 Re: Dark Discussions at Cafe Infinity » So how was your school year/ semester ??? » 2007-06-01 20:29:34

Laterally Speaking wrote:

Kinda like any subject.

My classes for this year were English, Spanish, French, Math, History, Geography, Civics, Physics, Technology, Art, Latin, Biology, Geology, and Sports. The days here start at 8:30AM and end at 5:00PM. There is , luckily, a lunch break from 12:30 to 2:00. Each class lasts about 1 hour, so it's 7 hours of class a day.

Woah dude, where do you get the time to do homework for all this?

#992 Re: This is Cool » The Future of our World » 2007-06-01 04:49:17

Yeah that's what I first thought when I saw it! It really adds to the atmosphere, and my favorite pic is of the Andromeda in the night sky!

#994 Re: Help Me ! » Arrangements » 2007-06-01 04:26:36

Right, thanks everyone

#995 Help Me ! » Arrangements » 2007-06-01 03:45:08

Identity
Replies: 4

Find all possible arrangements of the word PIGEON so that the vowels are in alphabetical order.

#996 Re: Dark Discussions at Cafe Infinity » So how was your school year/ semester ??? » 2007-06-01 03:43:39

Yeah it's pretty difficult, but as long as you do all the substantial homework the exam isn't too hard.

#997 Re: Dark Discussions at Cafe Infinity » So how was your school year/ semester ??? » 2007-05-31 21:16:25

Heh... exams coming up in about... a week, 6 of them: 2 Maths, english, chinese, international business, web authoring... -.- werkwerkwerk

#998 Re: Help Me ! » Australian Mathematics Competition » 2007-05-31 00:22:21

Sorry,  don't have any senior papers, but here are some intermediate ones. The questions in the hard section might still hopefully be relevant to your competition. It's in this thread:
http://www.mathsisfun.com/forum/viewtop … 841#p72841

#1000 Re: Dark Discussions at Cafe Infinity » Long words! » 2007-05-30 18:41:35

pnuemonoultramicrosopsiliconvolcaniosis is the longest one I can say off by heart.

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