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91Ó°ÊÓ

There are 2504 computer science students at a school. Of these, 1876 have taken a course in Java, 999 have taken a course in Linux, and 345 have taken a course in C. Further, 876 have taken courses in both Java and Linux, 231 have taken courses in both Linux and C, and 290 have taken courses in both Java and C. If 189 of these students have taken courses in Linux, Java, and C, how many of these 2504 students have not taken a course in any of these three programming languages?

Short Answer

Expert verified
898 students have not taken a course in Java, Linux, or C.

Step by step solution

01

- Define Variables

Let: A = number of students who have taken a Java course = 1876B = number of students who have taken a Linux course = 999C = number of students who have taken a C course = 345A ∩ B = number of students who have taken both Java and Linux = 876A ∩ C = number of students who have taken both Java and C = 290B ∩ C = number of students who have taken both Linux and C = 231A ∩ B ∩ C = number of students who have taken all three courses = 189
02

- Use Inclusion-Exclusion Principle

The Inclusion-Exclusion Principle formula for three sets is: \[|A \, \cup \ B \, \cup \, C| = |A| + |B| + |C| - |A \, \cap \, B| - |A \, \cap \, C| - |B \, \cap \, C| + |A \, \cap \, B \, \cap \, C|\]Substitute the given values:\[|A \, \cup \ B \, \cup \, C| = 1876 + 999 + 345 - 876 - 290 - 231 + 189\]
03

- Calculate Total Overlap

Calculate the total number of students who have taken at least one of the courses:\[|A \, \cup \ B \, \cup \, C| = 3003 - 1397 = 1606\]
04

- Find Students Who Have Not Taken Any Course

Subtract the number of students who have taken at least one course from the total number of students to find those who have not taken any course:\[2504 - 1606 = 898\]

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

set theory
Set theory is a fundamental concept in mathematics, focusing on the study of collections of objects, known as sets. In our exercise, we use sets to organize students by the courses they have taken. Each set represents a group of students who have taken a specific course: Java, Linux, or C. The powerful part of set theory is its ability to handle operations like unions and intersections.
For instance, if we have two sets A and B:
  • A = {students taking Java}
  • B = {students taking Linux}
The union (A ∪ B) includes all students taking either course. The intersection (A ∩ B) consists of students taking both courses. Understanding these basics is crucial for solving problems involving multiple groups, like finding those who haven't taken any courses.
overlapping sets
Overlapping sets occur when some elements belong to more than one set. In our exercise, students overlap in the courses they’ve taken. For example:
  • A ∩ B = 876 (students who took both Java and Linux)
  • A ∩ C = 290 (students who took both Java and C)
  • B ∩ C = 231 (students who took both Linux and C)
Furthermore, a subset of students might belong to all three courses, represented by A ∩ B ∩ C = 189. Managing these overlaps is where the Inclusion-Exclusion Principle becomes crucial. It helps us account for these overlaps effectively so that we do not double-count any students.
discrete mathematics
Discrete mathematics deals with distinct and separate values, often essential in computer science and combinatorics. In our problem, we use discrete math to solve a practical scenario using sets, combinations, and principles of counting. The Inclusion-Exclusion Principle is particularly relevant here. This principle helps us find the count of a union of sets by including the sizes of the sets and excluding the sizes of their pairwise and three-way intersections. Discrete mathematics provides the infrastructure for solving these well-defined, countable problems in a structured way.
problem-solving
Problem-solving in mathematics often involves structured steps to reach a solution. Here, let's break it down:
  • Define variables to name each set of students.
  • Apply the Inclusion-Exclusion Principle formula to find the total number of students in at least one course.
  • Compute the sum and subtract the overlaps from the triple intersection.
  • Finally, subtract this result from the total number of computer science students to find how many haven't taken any of the courses.
Steps like these make complex problems approachable. The key is to systematically break down the data, apply mathematical principles, and methodically solve the task.

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