Combinations Definition and 401 Threads
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A Possible number of chess games
Why is it so much hard to precisely estimate the number of possible games? Can a reliable quantum computer do this task? or do we need a universal computer? What ever universal computer may be, of course. https://perso.uclouvain.be/jean-charles.delvenne/WhatIsComputer.pdf- mad mathematician
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- Chess Combinations Games
- Replies: 20
- Forum: General Math
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Enabling the Combinations Calculator in Alexa?
On https://www.amazon.com/worldengine-Combinations-Calculator/dp/B01GSTMZ4U?tag=pfamazon01-20 I found the command as indicated in the Summary. The Alexa in question (of a student of mine -- I am not very familiar with Alexa) would answer other calculation questions, but not this one. Is this an...- nomadreid
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- Calculator Combinations
- Replies: 4
- Forum: Computing and Technology
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Solve the given problem involving conditional probability
Phew! took time to figure this out...i guess there may be a way to use combinations or markov process i do not know... anyway, it was pretty straightforward, we have the ##P_r(w) = \dfrac{n-3}{n}## from box ##X## and this will result in ##P_r(w) = \dfrac{4}{n+1}## in box ##Y##. Together i...- chwala
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- Combinations Markov process Probability
- Replies: 32
- Forum: Precalculus Mathematics Homework Help
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Partial Permutation, Combination question for buying dogs at the pet store
TL;DR Summary: A pet store has 5 Chihuahua, 3 Fox and 4 Poodle. A person wants to buy 7 dogs. How many ways for the person to choose and buy with at least 3 Chihuahua and 2 Poodle. There're C(5,3)*C(4,2) ways to buy dogs with at least 3 Chihuahua and 2 Poodle. There're C(7,2) ways to buy dogs...- Memo
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- Combinations
- Replies: 19
- Forum: Precalculus Mathematics Homework Help
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Probability using combinations or alternatives
I have attempted the solution above and I am fairly sure that it is correct. My question is the following: What am I calculating if I multiply 4/52 x 3/51 x 4/50 x 3/49 = 144/ 6,497,400 = 0.002%. I got the correct answer by following the principles of combination probabilities, but intuitively...- njh
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- Combinations Probability
- Replies: 12
- Forum: Precalculus Mathematics Homework Help
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Finding possible combinations of capacitors given circuit capacitance
For this problem, The solution is, Is the only way of finding the possible combinations is by drawing out circuit diagrams? Many thanks!- member 731016
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- Capacitance Capacitors Circuit Combinations
- Replies: 3
- Forum: Introductory Physics Homework Help
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I don't understand transistors in combinations .... Or maybe basics ....
Hello everybody ! I do have a problem understanding transistor. I know how these solve and work : I know some basics like the voltage on Rb is Vbb - 0,7V. Or something like this. I also Know that the maximal current in this transistor is "defined" by the resistor in the collector which is...- Xenon02
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- Basics Combinations Transistors
- Replies: 68
- Forum: Electrical Engineering
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Solve this problem that involves combinations
My interest is on part b only. I am seeking alternative approach to the problem. This was a tricky question i guess. Find my approach below; ##5C3×4C2 ##{senior cousin included and junior not included}+ ##5C4×4C1##{ senior cousin not included, Junior cousin included}+##5C4×4C2##{both NOT...- chwala
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- Combinations
- Replies: 1
- Forum: Precalculus Mathematics Homework Help
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Engineering Series-Parallel Combinations of Inductors
I am not sure where I made the mistake. If someone could point that out that would be much appreciated!- johnsmith7565
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- Combinations Inductors
- Replies: 3
- Forum: Engineering and Comp Sci Homework Help
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MHB How Many Unique Chocolate Combinations Can You Create?
There are 10 different chocolates and you want to buy three of them. However, you cannot pick a pair of chocolate more than once. How many different choice you can make??- Hypatia1
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- Choices Combinations
- Replies: 6
- Forum: General Math
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A Number of unequal integers with sum S
Hello, I've been trying to solve this problem for a while, and I found a technical solution which is too computationally intensive for large numbers, I am trying to solve the problem using Combinatorics instead. Given a set of integers 1, 2, 3, ..., 50 for example, where R=50 is the maximum...- Jarfi
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- Combinations Integers Sum Sums
- Replies: 12
- Forum: Set Theory, Logic, Probability, Statistics
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I Limit of limits of linear combinations of indicator functions
I have a sequence of functions ##0\leq f_1\leq f_2\leq ... \leq f_n \leq ...##, each one defined in ##\mathbb{R}^n## with values in ##\mathbb{R}##. I have also that ##f_n\uparrow f##. Every ##f_i## is the limit (almost everywhere) of "step" functions, that is a linear combination of rectangles...- Unconscious
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- Combinations Functions Limit Limits Linear Linear combinations Measure theory Real analysis
- Replies: 3
- Forum: Calculus
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MHB Game Night : Number of combinations
Hey! 😊 Sarah, Alex and Mary meet at Tom for a game night. a) The first game is a board game in which six game colors (red, green, yellow, blue, violet, orange) are possible. Each of the players chooses a color in turn. (Each color can only be assigned once.) How many different color...- mathmari
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- Combinations Game
- Replies: 14
- Forum: Set Theory, Logic, Probability, Statistics
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MHB Counting Color Combinations in 12 Triangles
There are 12 triangles (picture). We color each side of the triangle in red, green or blue. Among the $3^{24}$ possible colorings, how many have the property that every triangle has one edge of each color?- maxkor
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- Color Combinations Counting Triangles
- Replies: 3
- Forum: General Math
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I Analytical formula for the number of patterns by using combinations?
A 4×3 matrix which has all elements empty, now I select any two consecutive elements until all elements are selected. I assign an index number (1 to 12) to the matrix element, in one row there are only 1,2,3 elements and 3 & 4 are not consecutive. for example, if I select index 1 & 2 of the...- Sahil_John
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- Analytical Combinations Combinatorics Formula Patterns
- Replies: 12
- Forum: Set Theory, Logic, Probability, Statistics
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How many combinations? (High school math problem)
Summary:: Year 11 Extension 1 Math problem (Australia) How many combinations can be made from a 4 digit pin code if we can only use two numbers to form our pin code, and we MUST use 2 distinct numbers. E.g. 1112, 4334, 9944, 3232. But NOT 1111, 2113, 0992 etc. We're using the numbers 0-9 and...- YouAreAwesome
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- Combinations Probability School
- Replies: 20
- Forum: Precalculus Mathematics Homework Help
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B Combinations of 6 taken 4 at a time
the calculation 6C4 shows 15 but what if all sets are to be distinct? meaning 1,2,3,4 is the same as 4,3,2,1. I made a tree diagram and i get 10... assuming i did that correctly...?- Vector1962
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- Combinations Time
- Replies: 2
- Forum: Set Theory, Logic, Probability, Statistics
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Combinations: exam question distribution
I think the idea is to first count the number of ways the questions are passed out without restrictions and then subtract the number of ways the two easy questions are together. Call each student ##s_1,s_2,s_3##. We know their total number of questions is 8, so ##s_1+s_2+s_3 = 8 : s_1,s_2,s_3 >...- member 428835
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- Combinations Distribution Exam
- Replies: 3
- Forum: Precalculus Mathematics Homework Help
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MHB Matrices.......whose null space consists all linear combinations
$ v=\left[\begin{array}{r} -3\\-4\\-5\\4\\-1 \end{array}\right] w=\left[\begin{array}{r} -2\\0 \\1 \\4 \\-1 \end{array}\right] x=\left[\begin{array}{r} 2\\3 \\4 \\-5 \\0 \end{array}\right] y=\left[\begin{array}{r} -2\\1 \\0 \\-2 \\7 \end{array}\right] z=\left[\begin{array}{r} -1\\0 \\2 \\-3...- karush
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- Combinations Linear Linear combinations Null space Space
- Replies: 3
- Forum: Linear and Abstract Algebra
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Algebra High school courses on Permutations and combinations
Can you give me some high school papers or courses on p and c . I have a good source for problems but need a concise and compact course covering concepts. Thanks!- sahilmm15
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- Combinations Courses High school Permutations School
- Replies: 4
- Forum: Science and Math Textbooks
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MHB Combinations / Sets of objects
Hi, I am looking for a solution that generates combinations of objects from a series of objects in a set. For example, {Apple, Pear, Orange} should bring back Apple Pear Orange Apple, Pear Apple, Pear, Orange, Apple, Orange ... Items in the series should not repeat (i.e. Apple, Orange /...- arno100
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- Combinations Sets
- Replies: 1
- Forum: General Math
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Probability Questions: Union, Intersection and Combinations
Question 1: a) T' is the complementary event of T Therefore, T'=1-T In set T = {3,6,9,12} P(T)=4/12 =1/3 P(T')=1-1/3=2/3 b) The addition rule states; P(A ∪ B)=P(A)+P(B)-P(A⋂B) Therefore, P(S ∪ E) = P(S)+P(E)-P(S⋂E) S={1,4,9} P(S)=3/12=1/4 E={2,4,6,8,10,12} P(E)=6/12=1/2 (S⋂E)={4} P(S⋂E)=1/12...- AN630078
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- Combinations Intersection Probability Union
- Replies: 16
- Forum: Calculus and Beyond Homework Help
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I Closure in the subspace of linear combinations of vectors
This is the exact definition and I've summarized it, as I understand it above. Why is it, that for elements in the third subspace, closure will be lost? Wouldn't you still get another vector (when you add two vectors in that subspace), that's still a linear combination of the vectors in the...- Phys12
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- closure Combinations Linear Linear combinations Subspace Vectors
- Replies: 2
- Forum: Quantum Physics
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License Plate Combinations: Clarifying the Math
I have a question and searched about at google and found an answer which I don't make sure. If there is 26 letters and 10 digits; my answer is: first letter: 1 way(which is A) second letter: 26 way third letter: 26 way first digit: 1 way(which is 1) second digit 1 way(which is 2) third digit: 10...- requied
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- Combinations Counting problem Permutation & combination Plate
- Replies: 36
- Forum: Precalculus Mathematics Homework Help
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A Why Proton & Neutron Contain 3 Quarks - Not 2 or 4?
Proton and neutron are made up of three quarks (uud and udd). Why aren't there particles uuu or ddd?- mathman
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- Combinations Quark
- Replies: 7
- Forum: High Energy, Nuclear, Particle Physics
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MHB Possible combinations for six digit license plates, numbers 0-9 and letters a-z.
Hi, I'm not sure if this is the correct forum so if I need to post elsewhere please let me know. I'm having trouble with calculating the possible combinations for six digit license plates, numbers 0-9 and letters a-z. I know the overall combinations are 1,947,792 when repetition is allowed...- Mackenzie3
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- Combinations Numbers Plates
- Replies: 1
- Forum: General Math
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The most likely structure from combinations of these atoms
an element (we will call it X) got a cofiguration of 1##s^2##2##s^2##2##p^6##3##s^2##s##p^3## what molecule is moste likely to happened between this element and Mg? 1.MgX 2.##Mg_2##X 3.Mg##X_2## 4.##Mg_3## ##X_2## how do i do it?with lewis structure?just check what structure makes the most... -
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Proving the Minimum Value of Combinations: Odd vs. Even n
I know nCn/2 = n!/((n/2)!)^2 = 2^(n/2)(1.3.5...n-1) but I am not getting why it's the least one.- Crystal037
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- Combinations Value
- Replies: 27
- Forum: Precalculus Mathematics Homework Help
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I How to answer a Combinations question
Question: When playing Lotto 649, you must pick six numbers from the numbers 1, 2, …, 49. In how many ways can you do this? My attempt n!/r!(n-r)! = 49!/6!(49-6)! (49x48x47x46x...x1)/(6x5x4x3x2x1)(43x42x41x40x...x1) =0.06 . (edit: i redid the question and just made it (49x48x47x46x45x44)/(6!)...- Biochemgirl2002
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- Combinations
- Replies: 4
- Forum: Set Theory, Logic, Probability, Statistics
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How many ways can 5 prizes be distributed among 4 boys and 3 dividers?
the first boy has 6 ways, either he wins 0 or 1 or 2 or 3 or 4 or 5 ways According to the first boy, the second boy also has 0 or 1 or 2 or 3 or 4 or 5 chances According to the first and second boy, the other boy also has 0 or 1 or 2 or 3 or 4 or 5 chances. So, the answer should be 4(either of...- Crystal037
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- Combinations Permutations
- Replies: 22
- Forum: Precalculus Mathematics Homework Help
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B Is Permutation and Combination Challenging to Learn?
Summary: Is 'Permutation and combination' hard to understand ? I am facing difficulties in understanding this concept. So I would like to ask some questions to enhance my knowledge in this topic. My questions are- Does it require time to grasp this concept? Is it normal to get confused? How...- Kaushik
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- Combinations Permutations
- Replies: 28
- Forum: Set Theory, Logic, Probability, Statistics
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I Linear combinations of atomic orbitals
So I've been looking at covalent bonds and come across the approx you can do of the molecular orbital for ##H^+_2## by just summing two 1s orbitals, the method is called the linear combinations of atomic orbitals, and you get what is below which I believe is exact in this case since the 1s...- Avardia
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- Atomic Atomic orbitals Combinations Linear Linear combinations Orbitals
- Replies: 1
- Forum: Atomic and Condensed Matter
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MHB How to exclude combinations for defined sequences?
Please can anyone help with the below problem? It’s an interesting problem but please bear with me as i don't have much math background. A factory’s product is sampled once per month every month by its quality inspection team. The factory is allowed up to 2 product failures per ROLLING 12...- Josefk
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- Combinations Sequences
- Replies: 1
- Forum: General Math
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I Affine hull and affine combinations equivalence
Let ##X = \{x_1 , \dots , x_n\}##. Then ##\text{aff}(X) = \text{intersection of all affine spaces containing X}##. Let ##C(X)## be the set of all affine combinations of elements of ##X##. We want to show that these two sets are equal. First we focus on the ##\text{aff}(X) \subseteq C(X)##...- Mr Davis 97
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- Combinations Equivalence
- Replies: 7
- Forum: Linear and Abstract Algebra
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MHB Find a recursive formula for the number of combinations
I have some question integrating between combinatorics and recursive formulas.Generally, I have some difficulty with the concept of recursion, as well as with the recursion in programming unfortunately.I have some question to solve, and maybe you can guide me:Find a recursive formula and a...- CStudent
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- Combinations Formula
- Replies: 3
- Forum: Set Theory, Logic, Probability, Statistics
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Other Highschool Book for Permutations & Combinations
Can someone please tell me what good book for a high school student on permutation and combination? Thank you- askor
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- Book Combinations Highschool Permutations
- Replies: 1
- Forum: Science and Math Textbooks
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B Maximize Your Odds: Choosing Winning Lotto Combinations from 1 to 58
I bought 16 tickets recently and didn't even get 3 digits (out of 6) right. The lotto is from 1 to 58. You choose 6 numbers. The prize is 12 million dollars. How do you compute the probability to get 6 numbers out of 58 numbers? Any tips what combinations to get? I chose many with numbers...- kiki_danc
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- Combinations
- Replies: 15
- Forum: Set Theory, Logic, Probability, Statistics
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Finding no. of combinations for the situation
Homework Statement Refer the image Homework Equations Equations for permutations and combinations The Attempt at a Solution Let x be the no. of questions that turned out to be correct. So total score will be 3x-(10-x)=4x-10. The value of this expression must be from the given set and since x...- ubergewehr273
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- Combinations Combinatorics Permutations
- Replies: 5
- Forum: Precalculus Mathematics Homework Help
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MHB Puzzle Game - How Many Combinations - How Long To Solve
For this puzzle game: MillionPuzzleGame.com I'd like to check I worked out the number of combinations correctly. Also, how long would a computer take to solve it?- benjimon
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- Combinations Game Puzzle
- Replies: 1
- Forum: General Math
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Statistics Permutations and Combinations
Homework Statement The back row of a cinema has 12 seats, all of which are empty. A group of 8 people including Mary and Francis, sit in this row. Find the number of ways they can sit in these 12 seats if a) There are no restrictions b) Mary and France's do not sit in seats which are next to...- resurgance2001
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- Combinations Permutation & combination Permutations Statistics
- Replies: 8
- Forum: Calculus and Beyond Homework Help
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Which of the following combinations would act as buffered solutions
Homework Statement Which of the following combinations would act as buffered solutions? a. HCl and NaCl b. CH_3COOH and KCH_3COO c. H_2S and NaHS d. H_2S and Na_2S Homework Equations none really... The acid needs to be weak and the base strong though. The Attempt at a Solution HCl is one...- JessicaHelena
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- Acid Act Base Buffer Combinations
- Replies: 5
- Forum: Biology and Chemistry Homework Help
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B Combinations of n elements in pairs
Hey! C^2_2 = 1\:\:\:C^2_3 = 3\:\:\:C^2_4 = 6\:\:\:C^2_5 = 10 \\ We\:can\:see\:that\:\:\:C^2_n = C^2_{n-1} + (n-1),\:let's\:try\:n = 5 \\ C^2_5 = C^2_4 + (5 - 1) \\ = C^2_3 + (4 - 1) + (5 - 1) \\ = C^2_2 + (3 - 1) + (4 - 1) + (5 - 1) \\ = 1 + (3 - 1) + (4 - 1) + (5 - 1) \\ C^2_5 = (1 - 1) + (2 -...- archaic
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- Combinations Elements
- Replies: 2
- Forum: Set Theory, Logic, Probability, Statistics
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I Combinatorics & probability density
Suppose we have two boxes, each containing three types of balls. On each ball there's written a number: First box: 1, 2, 3 Second box: 4, 5, 6 We don't know how many balls of each type there are, but we know the probability of taking out a specific one, so that we can make a graph showing the...- Cathr
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- Balls Combinations Combinatorics Density Probability Probability density
- Replies: 2
- Forum: Set Theory, Logic, Probability, Statistics
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Probability No Member Gets >1 Medal: Math Club
Homework Statement There are 15 members of a maths club. There are 4 different medals to be randomly given to the members of the club. What is the probability that no member will receive more than one of the medals. Homework Equations Try to find the number of combinations where no member...- resurgance2001
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- Combinations Member Probability
- Replies: 4
- Forum: Calculus and Beyond Homework Help
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How Can Optimal Control Schemes Enhance Energy Storage System Combinations?
I'm currently working on combining energy storage systems like flywheels and batteries to balance consumption/regeneration. I've been looking at using an optimal control scheme so that a cost function can be tailored to our wishes. I'm curious about what other people in this field have been...- Liferider
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- Batteries Battery Combinations Control Energy Energy storage Flywheel Optimal control Storage
- Replies: 7
- Forum: Electrical Engineering
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Combination Question on seating
Homework Statement In how many different ways can you seat 11 men and 8 women in a row if no two women are to sit together? Homework Equations I have the combination and permutation equations The Attempt at a Solution I assume that given the context of this question if I have two, three...- RoboNerd
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- Combination Combinations
- Replies: 18
- Forum: Calculus and Beyond Homework Help
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Cheese shop combination question
Homework Statement Question: A cheese shop carries a large stock of 34 kinds of cheese. By the end of the day 48 cheese sales have been made and the items sold must be restocked. How many different restocking orders are possible? Homework Equations Combination and permutation equations The...- RoboNerd
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- Combination Combinations
- Replies: 15
- Forum: Calculus and Beyond Homework Help
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Combinations possible when choosing 4 or 5 team members from
Homework Statement How many combinations of people are there if you choose 4 or 5 from a group of 10? Homework Equations Relies on binomials The Attempt at a Solution binomial (10,4) = binomial (10,6) = 210 But when choosing 5 the answer is binomial (10,5) / 2 = 126 Why do I need to divide by 2?- zimbabwe
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- Binomial Combinations Members
- Replies: 2
- Forum: Calculus and Beyond Homework Help
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General formula for a combination of four categories
Homework Statement Say I have four categories which make up a "whole" that I'll call a unique "deal". Each deal can have "I" properties, "J" investors, "K" mortgages, and "L" credit lines, where "I" and "J" must be integers greater than zero and "K" and "L" are non-negative integers (i.e. 0 or...- AirRecce
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- Combination Combinations Formula General Probability Statistics
- Replies: 3
- Forum: Calculus and Beyond Homework Help
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B The number of possible combinations with a constraint
Hello , i was doing one of Euler project programming problems the other day , and i came across this one . i tried everything i know about probability , i tried combinations and everything , and i just couldn't get something logically fit to solve this . i tried to ignore this but i just...- Bayoudh101
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- Combinations Constraint
- Replies: 2
- Forum: General Math