Counting Definition and 413 Threads

I want to find out how many paricles on random move passing through a little hole ? There is no condition or force acting on eachof them. :biggrin: :biggrin:Thanks guys:biggrin: :biggrin:

Please help I have ALOT of questions! 1.)Starting at 888 and counting backward by 7, a student counts 888, 881 and 874, and so on. Which of the following numbers will be included? a) 35 b) 34 c) 33 d) 32 e) 31 Ok, so I by using the calcuator the aswer is 34, but how would you calcuate...

Counting Game This forum word game is simple. You start of with "1" and the next person posts the number following it (2), the next posts the number following it (3) and so on. No double posting If an incorrect number is posted, then carry on with the correct number. I'll start: 1...

I'm doing a compton scattering experiment, and I'm ahving trouble finding a good analytical way of determining where the peak is with its associated error. Its a counting experiment, so we use Poisson statistics, and we have the output of counts per channel over a range of 512 channels, each...

Do you know of an attempt to disprove the existence of a formula which predicts all prime numbers, as opposed to the accustomed attempt to derive one?

I am working on a problem in which there are 100 widgets. I need to find how many samples of size 5 there are, which I found to be 75,287,520. No problem there. I am not sure how to go about the next part, however. In the original set of 100 widgets, 3 are broken. How many of the samples of...

I hope that some of the folks (Mike, Howard, Patrick, Robin) who have engaged in the other threads [1][2][3] on outcome counting (ie Patrick's APP) see this thread. Starting with the Feynman path integral formulation of ordinary quantum mechanics, it is pretty straightforward to derive...

I need java to read a string and count how many characters are in it. I know there's some class that can do this. What is it?

imagine a 8 letter word, how many possibilities are there to arrange letters in the alphabet (26) that start with BO(in that order) OR end with BO (in that order), if letters can be repeated? This is my work: 1 * 1 * 26 * 26 * 26 * 26 * 26 * 26 = 26^6 + 26 * 26 * 26 * 26 * 26 * 26 *...

So, I'm currently looking for a job. I've been telling myself all through school that my current car has to last me, and it has... barely. It currently has no ABS (the modulator is bad, but the brakes still work) so it can't go through the Maryland emissions test which is due. It is leaking oil...

Some my puzzles of “coincidence counting” When I read literatures concerning with two-photon interference experiment, the “two-photon interference patterns” are always got by means of so called” coincidence counting”. My questions are: What is the coincidence counting? What the essential is the...

hi, I have been trying to solve the following questions (and similar) for 2 hours now without any major success. the questions are: 1) In how many different ways can 7 different books be arranged in a row if a. 3 specific books must be together b. two specified books must occupy the ends (I...

http://www.gamespot.com/news/6141517.html Is it just me or is that a lot of people playing one game. Whats so special about World of Warcraft anyway? Any hardcore WoW players on PF.

I have the definition that if F is a finite field then a \in F is a primitive root if ord(a) = |F|-1. Now what I don't understand is how exactly are there \phi(|F|-1) primitive roots? (Note: This material is supposed not to use any group theory.)

Is there a way to systematic way of counting the number of distinct homomorphisms from one ring to another?

Attempts to make the Born rule "emerge" explicitly from outcome counting I would like to compare and contrast the various attempts to date to reconstruct the MWI so that it: 1) assumes outcome counting instead of the Born rule, but also 2) makes correct experimental predictions. This is an...

A typical stat mech. question is the following: If I have 5 bosons and energy E to divide among the bosons, what is the total number of possible configurations? I can't remember this answer, so if someone reading this can post it that would be appreciated. Now, I want to ask a slightly...

Prime counting function-- no error. I have developed a prime counting function with no error; it returns the exact number of primes equal to or less than any number one chooses. I am rather ignorant of progress in this field... Has this been done before? Please, ignore any skepticism you...

I have a question about an example in my physics notes. It considers Nitrogen at room temperature and calculates p*r and finds this to be greater than h-bar and so it is consistent with the uncertainty principle: p*r = 2.4*10^-26 > hbar = 1*10^-27 It says at room temperature the momentum...

How many americans still drive thoughs old V8 tanks ??

i have discovered a formula for \pi(x^{a}) being Pi the prime number counting function in terms of a triple integral...but you wll say..this is already made what is this good for?..in fact if you knew \pi(x^{a}) with a total error O(x^d) by setting a=Ad and making A--->oo (infinite) the total...

This question seems easy, but I don't understand what it's mean with "without making change". Could someone help me? If you have 2 dollars, 2 quarter and 3 nickels: a) how many different sums can you pay without making change? b) Change the quarters into dimes and answer again...

Could someone help me with this question ? There are two locks on the door and the keys are among the six different ones you carry in your pocket. In a hurry you dropped one somewhere. a) What is the probability that you can still open the door ? b) What is the probability that the...

Could someone help me with this question ? There are two locks on the door and the keys are among the six different ones you carry in your pocket. In a hurry you dropped one somewhere. a) What is the probability that you can still open the door ? b) What is the probability that the...

I tried to write a function that would count all possible combinations that 4 couples could sit at a table assuming no man can sit next to his wife or next to another man. and 1wife and 1 husband sit at fixed positions. my problem doesn't compile and it says i either have too many or too few...

hmmmmmmmmmmm consider u r driving a train. there is 100 passengers in the train. at first station 50 more get into the train. 2nd station 27 more come in. but at the third station 45 left the train. 4th station no one leave or enter... 5th station 37 ins and 49 out. what is the name of...

I'm taking a crack at learning probability and statistics starting from the basics. Anyways here is the question. --- A fair coin is tossed 10 times and the sequence of scores recorded. How many sequences are there? How many sequences are there that contain exactly 3 heads? ---...

Hi everyone, I need to write a C code program to count the # of fuctions used in a certain file (function counter) Can you guys give me some hints/suggestions/ideas ? Thanks, Stan

I have encountered this set problem that seems simple enough at first glance, but I'm pretty ignorant about formal set theory and unsure of the rules. As I encountered it, this is how it was written: For any set S let P(S) denote all subsets of S. For example S={1,2} Then P(S)= {Ø, {1}...

I'm obviously not going to ask how many strings there are in the universe. :wink: my question. To each quark how many strings are there? Just one unique one? Billions and Billions? Also does Brian Greene's book. "The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for...

thare are 8 candidates for three student seats how many different ways can the seats be chosen? With the FCP I get 24 If it is a permutation I get 336 which is right and why? Thanks for the help

The kyoto Clock http://www.junkscience.com/

Is it fair to say combinations are just an application of the counting principle? I already understand that permutations are just an application of fundamental principle and that combinations are just an application of permutations. If it's fair to say that combinations are in fact, just an...

Is it fair to say combinations are just an application of the counting principle? I already understand that permutations are just an application of fundamental principle and that combinations are just an application of permutations. If it's fair to say that combinations are in fact, just an...

Hi, I wasn't sure how to approach this problem: You have 5 differently colored stones-red, orange, blue, green, purple. If the green stone cannot be placed at the front or the back of the sequence, how many possible arrangements can you make? I know that without the above restriction, the...

You have 10 pink balls and 15 purple balls. How many distinguishable arrangements are possible if two pink balls cannot be next to each other? I know the answer is 8008 but I have no idea how to get this

hi everyone... how many arrangements of this word "aabbcccdddd" is possible if we only use 3 of them? I know if we could use all of them it would just be 11!/(2!2!3!4!), but what if we only use 3? :confused: Thanks in advance

show that \frac{ ((n^2)!)!}{(n!)^{n+1}} is an integer. i was thinking of saying that there are so many people who can be put on a committee, etc etc which would make an integer. i don't think this is real hard but nothing is really jumping out at me

Is there a concise, easily calculable way to count the sum of all the paths from the lower left corner of a square of integer size to the upper right corner where you only move up or right in steps of 1 unit, PLUS all the partial paths? i.e. if you have a city with roads in a 10x10 grid (100...

The question is... How many subsets of a (2n+1)-element set have n elements or less? To figure this out I started by using a workable example. Obviously n must be small to keep the total number of subsets small. So I started with n=1 and so there are 8 total subsets. And of course in...

Is there a systematical way to count all the possible feynman diagram with vertices less than or equal to n...

1) If X is an n-element set and Y is an m-element set, how many functions are there from X to Y? I am not sure but I worked on this for a while and I come up with there are m^n possible functions. 2) There are five distinct computer science books, three distinct mathematics books and...

Prove: a group of even order must have an even number of elements of order 2

OK I'm unclear about how to use FCP to solve this problem: The final score in a hockey game is 5-2. How many different scores are possible at the end of the second period? :confused:

Problem details: I think if I pretend that N is also a number from 0-9, then there would be P(10, 7) numbers without repeats, but then that's too much and I'm not sure how I can subtract the number's that N is not supposed to have. The other way I was thinking is the last 6 numbers can be...

I refer you to a proposal about the finiteness of the integers: http://paulandellen.com/essays/essay089.htm How could this be? Everyone has assumed that the integers are infinite, yet a proof can be give to illustrate otherwise. Firstly we will use the characters necessary for expression of...

Here are my problems: 1) Suppose seven school children (3 girls and 4 boys) are lined up to board a school bus. Find the number of ways they could line up if no two boys are together. This arrangement would be BGBGBGB. So if I consider each BG as a unit, then there are 4! arrangements. But...

dear reader, here is a quick counting question: A counter near a long-lived radioactive source measures an average of 100 counts per minute. The probabilty that more than 110 counts will be recorded in a given one-minute interval is most nearly (A) zero (B) .001 (C) .025 (D) .15 (E) .5 I...

Dear members, here is a gre problem that I couldn't know how to tackle, any effort will be greatly appreciated. An experimenter measures 9934 counts during one hour from a radioactive sample. From this number the counting rate of the sample can be estimated with a standard deviation of most...

A set of blocks contains blocks of heights 1, 2, and 4 inches. Imagine constructing towers of piling block of different heights directly on top of one another. Let t(n) be the number of ways to construct a tower of height n inches. Find a recurrence relation for t(1), t(2), t(3)... Here's...