2024 Principle of inclusion exclusion

This formula makes sense to me again, but can someone please explain it to me in simple terms how the binomial theorem is even related to inclusion/exclusion? I've also seen proofs where examples substitute the x = 1 and y = -1 and we end up getting the binomial expansion to equal 0. I just don't see how we can relate that to PIE. Please help .... Stop and shop circular next week

The Inclusion-Exclusion Principle. The inclusion-exclusion principle is an important combinatorial way to compute the size of a set or the probability of complex events. It relates the sizes of individual sets with their union. Statement The verbal formula. The inclusion-exclusion principle can be expressed as follows:Apr 17, 2016 · You might take out those divisible by $2,3,5,7$ (all the primes up to $\sqrt{100}$). Doing this is a pretty straightforward includsion-exclusion counting, and this has the effect of counting the number of primes between $10$ and $100$. This video contains the description about principle of Inclusion and ExclusionSep 24, 2015 · How to count using the Inclusion/Exclusion Principle. This is Chapter 9 Problem 4 of the MATH1231/1241 Algebra notes. Presented by Daniel Chan from UNSW. Principle of Inclusion-Exclusion. The Principle of Inclusion-Exclusion (abbreviated PIE) provides an organized method/formula to find the number of elements in the union of a given group of sets, the size of each set, and the size of all possible intersections among the sets. 排容原理. 三個集的情況. 容斥原理（inclusion-exclusion principle）又称排容原理，在組合數學裏，其說明若 , ..., 為有限集，則. 其中表示的基數。. 例如在兩個集的情況時，我們可以通過將和相加，再減去其交集的基數，而得到其并集的基數。. The principle of inclusion and exclusion is very important and useful for enumeration problems in combinatorial theory. By using this principle, in the chapter, the number of elements of A that satisfy exactly r properties of P are deduced, given the numbers of elements of A that satisfy at least k ( k ≥ r) properties of P.Principle of Inclusion-Exclusion. The Principle of Inclusion-Exclusion (abbreviated PIE) provides an organized method/formula to find the number of elements in the union of a given group of sets, the size of each set, and the size of all possible intersections among the sets. In combinatorics, a branch of mathematics, the inclusion–exclusion principle is a counting technique which generalizes the familiar method of obtaining the number of elements in the union of two finite sets; symbolically expressed as where A and B are two finite sets and |S | indicates the cardinality of a set S . The formula expresses the fact that the sum of the sizes of the two sets may ... The Restricted Inclusion-Exclusion Principle. Let be subsets of . Then. This is a formula which looks familiar to many people, I'll call it The Restricted Inclusion-Exclusion Principle, it can convert the problem of calculating the size of the union of some sets into calculating the size of the intersection of some sets. Induction Step. Consider f(⋃i= 1r Ai ∩Ar+1) f ( ⋃ i = 1 r A i ∩ A r + 1) . By the fact that Intersection Distributes over Union, this can be written: At the same time, we have the expansion of the term f(⋃i= 1r Ai) f ( ⋃ i = 1 r A i) to take into account. So we can consider the general term of s s intersections in the expansion of f ...The Inclusion-Exclusion Principle. The inclusion-exclusion principle is an important combinatorial way to compute the size of a set or the probability of complex events. It relates the sizes of individual sets with their union. Statement The verbal formula. The inclusion-exclusion principle can be expressed as follows:is to present several deriv ations of the inclusion-exclusion formula and various ancillary form ulas and to give a few examples of its use. Let S be a set of n elements with n ≥ 1, and let S 1 ...The Restricted Inclusion-Exclusion Principle. Let be subsets of . Then. This is a formula which looks familiar to many people, I'll call it The Restricted Inclusion-Exclusion Principle, it can convert the problem of calculating the size of the union of some sets into calculating the size of the intersection of some sets.Oct 10, 2014 · The Principle of Inclusion-Exclusion. Example 1: In a discrete mathematics class every student is a major in computer science or mathematics , or both. The number of students having computer science as a major (possibly along with mathematics) is 25; By Bonferroni's inequalities, the terms in the inclusion-exclusion sum alternately under- and over-estimate the final value. You should be fine with just: $$ \lvert A_1 \cup A_2 \cup \ldots \cup A_n \rvert \ge \sum_i \lvert A_i \rvert - \sum_{i < j} \lvert A_i \cap A_j \rvert \ge \sum_i \lvert A_i \rvert - \sum_{i < j} a_{ij} $$ This bound can ...Nov 21, 2018 · A thorough understanding of the inclusion-exclusion principle in Discrete Mathematics is vital for building a solid foundation in set theory. With the inclusion-exclusion principle, there are generally two types of questions that appear in introductory and lower level Discrete Mathematics syllabi. These question types are: The inclusion-exclusion principle (like the pigeon-hole principle we studied last week) is simple to state and relatively easy to prove, and yet has rather spectacular applications. In class, for instance, we began with some examples that seemed hopelessly complicated.Jun 10, 2020 · So, by applying the inclusion-exclusion principle, the union of the sets is calculable. My question is: How can I arrange these cardinalities and intersections on a matrix in a meaningful way so that the union is measurable by a matrix operation like finding its determinant or eigenvalue. Jan 30, 2012 · Homework Statement Suppose that p and q are prime numbers and that n = pq. Use the principle of inclusion-exclusion to find the number of positive integers not exceeding n that are relatively prime to n. Homework Equations Inclusion-Exclusion The Attempt at a Solution The... Inclusion-Exclusion Selected Exercises Powerpoint Presentation taken from Peter Cappello’s webpage www.cs.ucsb.edu/~capello The principle of inclusion and exclusion is a counting technique in which the elements satisfy at least one of the different properties while counting elements satisfying more than one property are counted exactly once. For example if we want to count number of numbers in first 100 natural numbers which are either divisible by 5 or by 7 . Let ...Nov 21, 2018 · A thorough understanding of the inclusion-exclusion principle in Discrete Mathematics is vital for building a solid foundation in set theory. With the inclusion-exclusion principle, there are generally two types of questions that appear in introductory and lower level Discrete Mathematics syllabi. These question types are: Oct 12, 2015 · The way I usually think of the Inclusion-Exclusion Principle goes something like this: If something is in n of the S j, it will be counted ( n k) times in the sum of the sizes of intersections of k of the S j. Therefore, it will be counted. (1) ∑ k ≥ 1 ( − 1) k − 1 ( n k) = 1. time in the expression. TheInclusion-Exclusion Principle Physics 116C Fall 2012 TheInclusion-Exclusion Principle 1. The probability that at least one oftwoevents happens Consider a discrete sample space Ω. We deﬁne an event A to be any subset of Ω, which in set notation is written as A⊂ Ω. Then, Boas asserts in eq. (3.6) on p. 732 that1The inclusion-exclusion principle is similar to the pigeonhole principle in that it is easy to state and relatively easy to prove, and also has an extensive range of applications. These sort of ...This proves the principle of inclusion-exclusion. Although the proof seems very exciting, I am confused because what the author has proved is $1=1$ from the LHS and RHS. Thus, is this still a valid proof? We need to prove that the total cardinality of LHS is the RHS. The RHS produces a $1$ for each member of the union of the sets.This video contains the description about principle of Inclusion and Exclusion包除原理（ほうじょげんり、英: Inclusion-exclusion principle, principle of inclusion and exclusion, Principle of inclusion-exclusion, PIE ）あるいは包含と排除の原理とは、数え上げ組合せ論における基本的な結果のひとつ。. 特別な場合には「有限集合 A と B の和集合に属する ... Jun 10, 2015 · I want to find the number of primes numbers between 1 and 30 using the exclusion and inclusion principle. This is what I got: The numbers in sky-blue are the ones I have to subtract. The Inclusion-Exclusion Principle. The inclusion-exclusion principle is an important combinatorial way to compute the size of a set or the probability of complex events. It relates the sizes of individual sets with their union. Statement The verbal formula. The inclusion-exclusion principle can be expressed as follows:The question wants to count certain arrangements of the word "ARRANGEMENT": a) find exactly 2 pairs of consecutive letters? b) find at least 3 pairs of consecutive letters? I have the ans...Jun 15, 2015 · And let A A be a set of elements which has some of these properties. Then the Inclusion-Exclusion Principle states that the number of elements with no properties at all is. This is perfectly fine, but he finishes his two-page paper with a Generalized version of Inclusion-Exclusion Principle. Let t1, ⋯,tn t 1, ⋯, t n be commuting ... Inclusion/Exclusion with 4 Sets • Suppose you are using the inclusion-exclusion principle to compute the number of elements in the union of four sets. –Each set has 15 elements. –The pair-wise intersections have 5 elements each. –The three-way intersections have 2 elements each. –There is only one element in the intersection of all ... And let A A be a set of elements which has some of these properties. Then the Inclusion-Exclusion Principle states that the number of elements with no properties at all is. This is perfectly fine, but he finishes his two-page paper with a Generalized version of Inclusion-Exclusion Principle. Let t1, ⋯,tn t 1, ⋯, t n be commuting ...The Inclusion-Exclusion Principle (for two events) For two events A, B in a probability space: P(A ... Mar 28, 2022 · The principle of Inclusion-Exclusion is an effective way to calculate the size of the individual set related to its union or capturing the probability of complicated events. Takeaways Inclusion and exclusion criteria increases the likelihood of producing reliable and reproducible results. Last post was a proof for the Inclusion-Exclusion Principle and now this post is a couple of examples using it. The first example will revisit derangements (first mentioned in Power of Generating Functions); the second is the formula for Euler's phi function. Yes, many posts will end up mentioning Euler …Write out the explicit formula given by the principle of inclusion–exclusion for the number of elements in the union of six sets when it is known that no three of these sets have a common intersection. Mar 28, 2022 · The principle of Inclusion-Exclusion is an effective way to calculate the size of the individual set related to its union or capturing the probability of complicated events. Takeaways Inclusion and exclusion criteria increases the likelihood of producing reliable and reproducible results. The Restricted Inclusion-Exclusion Principle. Let be subsets of . Then. This is a formula which looks familiar to many people, I'll call it The Restricted Inclusion-Exclusion Principle, it can convert the problem of calculating the size of the union of some sets into calculating the size of the intersection of some sets.Lecture 4: Principle of inclusion and exclusion Instructor: Jacob Fox 1 Principle of inclusion and exclusion Very often, we need to calculate the number of elements in the union of certain sets. Assuming that we know the sizes of these sets, and their mutual intersections, the principle of inclusion and exclusion allows us to do exactly that. Feb 24, 2014 at 15:36. You could intuitively try to prove an equation by drawing four sets in the form of a Venn diagram -- say A1,A2,A3,A4 A 1, A 2, A 3, A 4, and observing the intersections between the circles. You want to find the cardinality of the union.Aug 4, 2013 · Last post was a proof for the Inclusion-Exclusion Principle and now this post is a couple of examples using it. The first example will revisit derangements (first mentioned in Power of Generating Functions); the second is the formula for Euler's phi function. Yes, many posts will end up mentioning Euler … Aug 31, 2019 · It seems that this formula is similar to an inclusion-exclusion formula? One approach I was thinking was an induction approach. Obviously if we take $|K|=1$ the formula holds. The induction step could be to assume it holds for $|K-1|-1$ and then simply prove the final result. Does this seem a viable approach, any other suggested approaches are ... Write out the explicit formula given by the principle of inclusion–exclusion for the number of elements in the union of six sets when it is known that no three of these sets have a common intersection. A thorough understanding of the inclusion-exclusion principle in Discrete Mathematics is vital for building a solid foundation in set theory. With the inclusion-exclusion principle, there are generally two types of questions that appear in introductory and lower level Discrete Mathematics syllabi. These question types are:The principle of inclusion-exclusion is an important result of combinatorial calculus which finds applications in various fields, from Number Theory to Probability, Measurement Theory and others. In this article we consider different formulations of the principle, followed by some applications and exercises.The lesson accompanying this quiz and worksheet called Inclusion-Exclusion Principle in Combinatorics can ensure you have a quality understanding of the following: Description of basic set theory ... Jan 30, 2012 · Homework Statement Suppose that p and q are prime numbers and that n = pq. Use the principle of inclusion-exclusion to find the number of positive integers not exceeding n that are relatively prime to n. Homework Equations Inclusion-Exclusion The Attempt at a Solution The... The principle of inclusion and exclusion is intimately related to Möbius inversion, which can be generalized to posets. I'd start digging in this general area. I'd start digging in this general area.Due to the duality between union and intersection, the inclusion–exclusion principle can be stated alternatively in terms of unions or intersections. For example, the number of multiples of three below 20 is [19/3] = 6; these are 3, 6, 9, 12, 15, 18. 33 = [999/30] numbers divisible by 30 = 2·3·. According to the Inclusion-Exclusion Principle, the amount of integers below 1000 that could not be prime-looking is. 499 + 333 + 199 - 166 - 99 - 66 + 33 = 733. There are 733 numbers divisible by ...I want to find the number of primes numbers between 1 and 30 using the exclusion and inclusion principle. This is what I got: The numbers in sky-blue are the ones I have to subtract.Lecture 4: Principle of inclusion and exclusion Instructor: Jacob Fox 1 Principle of inclusion and exclusion Very often, we need to calculate the number of elements in the union of certain sets. Assuming that we know the sizes of these sets, and their mutual intersections, the principle of inclusion and exclusion allows us to do exactly that. A thorough understanding of the inclusion-exclusion principle in Discrete Mathematics is vital for building a solid foundation in set theory. With the inclusion-exclusion principle, there are generally two types of questions that appear in introductory and lower level Discrete Mathematics syllabi. These question types are:Counting intersections can be done using the inclusion-exclusion principle only if it is combined with De Morgan’s laws of complementing. a) true. b) false. View Answer. 10. Using the inclusion-exclusion principle, find the number of integers from a set of 1-100 that are not divisible by 2, 3 and 5. a) 22. b) 25. c) 26.Full Course of Discrete Mathematics: https://youtube.com/playlist?list=PLV8vIYTIdSnZjLhFRkVBsjQr5NxIiq1b3In this video you can learn about Principle of Inclu...1 Answer. It might be useful to recall that the principle of inclusion-exclusion (PIE), at least in its finite version, is nothing but the integrated version of an algebraic identity involving indicator functions. 1 −1A =∏i=1n (1 −1Ai). 1 − 1 A = ∏ i = 1 n ( 1 − 1 A i). Integrating this pointwise identity between functions, using ... Inclusion-Exclusion Selected Exercises Powerpoint Presentation taken from Peter Cappello’s webpage www.cs.ucsb.edu/~capelloThis video contains the description about principle of Inclusion and Exclusion排容原理. 三個集的情況. 容斥原理（inclusion-exclusion principle）又称排容原理，在組合數學裏，其說明若 , ..., 為有限集，則. 其中表示的基數。. 例如在兩個集的情況時，我們可以通過將和相加，再減去其交集的基數，而得到其并集的基數。.In combinatorics, a branch of mathematics, the inclusion–exclusion principle is a counting technique which generalizes the familiar method of obtaining the number of elements in the union of two finite sets; symbolically expressed as where A and B are two finite sets and |S | indicates the cardinality of a set S . The formula expresses the fact that the sum of the sizes of the two sets may ... Inclusion/Exclusion with 4 Sets • Suppose you are using the inclusion-exclusion principle to compute the number of elements in the union of four sets. –Each set has 15 elements. –The pair-wise intersections have 5 elements each. –The three-way intersections have 2 elements each. –There is only one element in the intersection of all ... 1 Principle of inclusion and exclusion Very often, we need to calculate the number of elements in the union of certain sets. Assuming that we know the sizes of these sets, and their mutual intersections, the principle of inclusion and exclusion allows us to do exactly that. Suppose that you have two sets A; B.Number of solutions to an equation using the inclusion-exclusion principle 3 Given $3$ types of coins, how many ways can one select $20$ coins so that no coin is selected more than $8$ times.The inclusion exclusion principle forms the basis of algorithms for a number of NP-hard graph partitioning problems, such as graph coloring. A well known application of the principle is the construction of the chromatic polynomial of a graph. Bipartite graph perfect matchings By the principle of inclusion-exclusion, jA[B[Sj= 3 (219 1) 3 218 + 217. Now for the other solution. Instead of counting study groups that include at least one of Alicia, Bob, and Sue, we will count study groups that don’t include any of Alicia, Bob, or Sue. To form such a study group, we just need to choose at least 2 of the remaining 17 ... Counting intersections can be done using the inclusion-exclusion principle only if it is combined with De Morgan’s laws of complementing. a) true. b) false. View Answer. 10. Using the inclusion-exclusion principle, find the number of integers from a set of 1-100 that are not divisible by 2, 3 and 5. a) 22. b) 25. c) 26.By Bonferroni's inequalities, the terms in the inclusion-exclusion sum alternately under- and over-estimate the final value. You should be fine with just: $$ \lvert A_1 \cup A_2 \cup \ldots \cup A_n \rvert \ge \sum_i \lvert A_i \rvert - \sum_{i < j} \lvert A_i \cap A_j \rvert \ge \sum_i \lvert A_i \rvert - \sum_{i < j} a_{ij} $$ This bound can ...Mar 8, 2020 · The principle of inclusion-exclusion is an important result of combinatorial calculus which finds applications in various fields, from Number Theory to Probability, Measurement Theory and others. In this article we consider different formulations of the principle, followed by some applications and exercises. General Inclusion-Exclusion Principle Formula. The inclusion-exclusion principle can be extended to any number of sets n, where n is a positive integer. The general inclusion-exclusion principle ... The probabilistic principle of inclusion and exclusion (PPIE for short) is a method used to calculate the probability of unions of events. For two events, the PPIE is equivalent to the probability rule of sum: The PPIE is closely related to the principle of inclusion and exclusion in set theory.Feb 24, 2014 at 15:36. You could intuitively try to prove an equation by drawing four sets in the form of a Venn diagram -- say A1,A2,A3,A4 A 1, A 2, A 3, A 4, and observing the intersections between the circles. You want to find the cardinality of the union.Full Course of Discrete Mathematics: https://youtube.com/playlist?list=PLV8vIYTIdSnZjLhFRkVBsjQr5NxIiq1b3In this video you can learn about Principle of Inclu... The probabilistic principle of inclusion and exclusion (PPIE for short) is a method used to calculate the probability of unions of events. For two events, the PPIE is equivalent to the probability rule of sum: The PPIE is closely related to the principle of inclusion and exclusion in set theory.I want to find the number of primes numbers between 1 and 30 using the exclusion and inclusion principle. This is what I got: The numbers in sky-blue are the ones I have to subtract.The way I usually think of the Inclusion-Exclusion Principle goes something like this: If something is in n of the S j, it will be counted ( n k) times in the sum of the sizes of intersections of k of the S j. Therefore, it will be counted. (1) ∑ k ≥ 1 ( − 1) k − 1 ( n k) = 1. time in the expression.University of PittsburghThe inclusion-exclusion principle states that the number of elements in the union of two given sets is the sum of the number of elements in each set, minus the number of elements that are in both sets.排容原理. 三個集的情況. 容斥原理（inclusion-exclusion principle）又称排容原理，在組合數學裏，其說明若 , ..., 為有限集，則. 其中表示的基數。. 例如在兩個集的情況時，我們可以通過將和相加，再減去其交集的基數，而得到其并集的基數。.For example, the number of multiples of three below 20 is [19/3] = 6; these are 3, 6, 9, 12, 15, 18. 33 = [999/30] numbers divisible by 30 = 2·3·. According to the Inclusion-Exclusion Principle, the amount of integers below 1000 that could not be prime-looking is. 499 + 333 + 199 - 166 - 99 - 66 + 33 = 733. There are 733 numbers divisible by ...The principle of inclusion and exclusion was used by the French mathematician Abraham de Moivre (1667–1754) in 1718 to calculate the number of derangements on n elements. Since then, it has found innumerable applications in many branches of mathematics.Sep 14, 2018 · This formula makes sense to me again, but can someone please explain it to me in simple terms how the binomial theorem is even related to inclusion/exclusion? I've also seen proofs where examples substitute the x = 1 and y = -1 and we end up getting the binomial expansion to equal 0. I just don't see how we can relate that to PIE. Please help ... This set of Discrete Mathematics Multiple Choice Questions & Answers (MCQs) focuses on “Discrete Probability – Principle of Inclusion Exclusion”. 1. There are 70 patients admitted in a hospital in which 29 are diagnosed with typhoid, 32 with malaria, and 14 with both typhoid and malaria. Find the number of patients diagnosed with typhoid ...The Restricted Inclusion-Exclusion Principle. Let be subsets of . Then. This is a formula which looks familiar to many people, I'll call it The Restricted Inclusion-Exclusion Principle, it can convert the problem of calculating the size of the union of some sets into calculating the size of the intersection of some sets.

How can this be done using the principle of inclusion/exclusion? combinatorics; inclusion-exclusion; Share. Cite. Follow edited Nov 12, 2014 at 5:56. asked .... Abby youyou

The inclusion exclusion principle forms the basis of algorithms for a number of NP-hard graph partitioning problems, such as graph coloring. A well known application of the principle is the construction of the chromatic polynomial of a graph. Bipartite graph perfect matchings A well-known application of the inclusion–exclusion principle is to the combinatorial problem of counting all derangements of a finite set. A derangement of a set A is a bijection from A into itself that has no fixed points. Via the inclusion–exclusion principle one can show that if the cardinality of A is n, then the number of derangements isGeneral Inclusion-Exclusion Principle Formula. The inclusion-exclusion principle can be extended to any number of sets n, where n is a positive integer. The general inclusion-exclusion principle ... The principle of inclusion and exclusion is a counting technique in which the elements satisfy at least one of the different properties while counting elements satisfying more than one property are counted exactly once. For example if we want to count number of numbers in first 100 natural numbers which are either divisible by 5 or by 7 . Let ...Last post was a proof for the Inclusion-Exclusion Principle and now this post is a couple of examples using it. The first example will revisit derangements (first mentioned in Power of Generating Functions); the second is the formula for Euler's phi function. Yes, many posts will end up mentioning Euler …The way I usually think of the Inclusion-Exclusion Principle goes something like this: If something is in n of the S j, it will be counted ( n k) times in the sum of the sizes of intersections of k of the S j. Therefore, it will be counted. (1) ∑ k ≥ 1 ( − 1) k − 1 ( n k) = 1. time in the expression.The inclusion-exclusion principle is closely related to an historic method for computing any initial sequence of prime numbers. Let p1 , p2 , . . ., pm be the sequence consisting of the first m primes and take S = {2, 3, . . . , n}.Inclusion-Exclusion Selected Exercises. ... Exercise 14 Exercise 14 Solution The Principle of Inclusion-Exclusion The Principle of Inclusion-Exclusion Proof Proof ...Inclusion/Exclusion with 4 Sets • Suppose you are using the inclusion-exclusion principle to compute the number of elements in the union of four sets. –Each set has 15 elements. –The pair-wise intersections have 5 elements each. –The three-way intersections have 2 elements each. –There is only one element in the intersection of all ... The Inclusion-Exclusion Principle. The inclusion-exclusion principle is an important combinatorial way to compute the size of a set or the probability of complex events. It relates the sizes of individual sets with their union. Statement The verbal formula. The inclusion-exclusion principle can be expressed as follows:due to lack of time and prerequisites. Here we prove the general (probabilistic) version of the inclusion-exclusion principle. Many other elementary statements about probability have been included in Probability 1. Notice that the inclusion-exclusion principle has various formulations including those for counting in combinatorics.Using inclusion-exclusion principle to count the integers in $\{1, 2, 3, \dots , 100\}$ that are not divisible by $2$, $3$ or $5$ Ask QuestionHow to count using the Inclusion/Exclusion Principle. This is Chapter 9 Problem 4 of the MATH1231/1241 Algebra notes. Presented by Daniel Chan from UNSW.The principle of Inclusion-Exclusion is an effective way to calculate the size of the individual set related to its union or capturing the probability of complicated events. Takeaways Inclusion and exclusion criteria increases the likelihood of producing reliable and reproducible results.The inclusion exclusion principle forms the basis of algorithms for a number of NP-hard graph partitioning problems, such as graph coloring. A well known application of the principle is the construction of the chromatic polynomial of a graph. Bipartite graph perfect matchings In combinatorics, a branch of mathematics, the inclusion–exclusion principle is a counting technique which generalizes the familiar method of obtaining the number of elements in the union of two finite sets; symbolically expressed as where A and B are two finite sets and |S | indicates the cardinality of a set S . The formula expresses the fact that the sum of the sizes of the two sets may ... The way I usually think of the Inclusion-Exclusion Principle goes something like this: If something is in n of the S j, it will be counted ( n k) times in the sum of the sizes of intersections of k of the S j. Therefore, it will be counted. (1) ∑ k ≥ 1 ( − 1) k − 1 ( n k) = 1. time in the expression..

How can this be done using the principle of inclusion/exclusion? combinatorics; inclusion-exclusion; Share. Cite. Follow edited Nov 12, 2014 at 5:56. asked .... Abby youyou

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