/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 1 Suppose a family contains two ch... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Suppose a family contains two children of different ages, and we are interested in the gender of these children. Let \(F\) denote that a child is female and \(M\) that the child is male and let a pair such as FM denote that the older child is female and the younger is male. There are four points in the set \(S\) of possible observations: $$S=\\{F F, F M, M F, M M\\}$$ Let \(A\) denote the subset of possibilities containing no males; \(B\), the subset containing two males; and \(C,\) the subset containing at least one male. List the elements of \(A, B, C, A \cap B, A \cup B, A \cap C\) \(A \cup C, B \cap C, B \cup C,\) and \(C \cap \bar{B}\)

Short Answer

Expert verified
A={FF}; B={MM}; C={FM, MF, MM}; A∩B=∅; A∪B={FF, MM}; A∩C=∅; A∪C=S; B∩C={MM}; B∪C={FM, MF, MM}; C∩B̅={FM, MF}.

Step by step solution

01

Identify the Sets

First, identify the given sets:- Set \(S\): the set of all possible observations is \( \{FF, FM, MF, MM\} \).- Set \(A\): contains no males, hence \(A = \{FF\}\).- Set \(B\): contains two males, hence \(B = \{MM\}\).- Set \(C\): contains at least one male, hence \(C = \{FM, MF, MM\}\).
02

Find Intersections and Unions

Now we'll find the intersections and unions of the identified sets:- Intersection \(A \cap B\): There are no outcomes that are both set \(A\) and set \(B\), so \(A \cap B = \{\}\).- Union \(A \cup B\): Combine \(A\) and \(B\) to get \(A \cup B = \{FF, MM\}\).- Intersection \(A \cap C\): There are no outcomes that are both in \(A\) and \(C\), so \(A \cap C = \{\}\).
03

Calculate Additional Intersections and Unions

Let's calculate the additional intersections and unions:- Union \(A \cup C\): Combine \(A\) and \(C\) to get \(A \cup C = \{FF, FM, MF, MM\}\), which is the entire set \(S\).- Intersection \(B \cap C\): They have only one outcome in common, \(B \cap C = \{MM\}\).- Union \(B \cup C\): Combine \(B\) and \(C\) to get \(B \cup C = \{FM, MF, MM\}\).
04

Calculate Complement and Final Intersection

Finally, find the complement of \(B\) and the intersection with \(C\):- Complement \(\bar{B}\) of \(B\): All elements in \(S\) not in \(B\), \(\bar{B} = \{FF, FM, MF\}\).- Intersection \(C \cap \bar{B}\): This is \(\{FM, MF\}\) as they are common in \(C\) and \(\bar{B}\).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

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

Set Theory
Set theory is an essential part of mathematics that deals with the study of collections of objects. In probability theory, sets are used to represent different possible outcomes or events. For our exercise, the set \(S = \{FF, FM, MF, MM\}\) represents all possible combinations of two children's genders.
To understand the exercise's solution, we should grasp some basic operations of set theory:
  • Union \( (A \cup B) \): This operation combines all elements from sets \(A\) and \(B\). For example, \(A \cup B = \{FF, MM\}\) means we include all combinations where there are no males and where there are two males.
  • Intersection \( (A \cap B) \): This operation finds common elements between sets \(A\) and \(B\). For instance, \(A \cap B = \{\} \) indicates there are no common elements between these sets.
  • Complement \( (\bar{B}) \): Represents all elements not in set \(B\). In our example, \(\bar{B} = \{FF, FM, MF\}\).
The correct understanding and application of these operations enable us to analyze and deduce the potential outcomes correctly.
Combinatorics
Combinatorics is the field of mathematics focused on counting, arranging, and combining objects. In our problem, combinatorics helps us to find all possible combinations of two children with respect to their genders. The approach taken involves creating a set of all possible combinations.
  • We denote female as \(F\) and male as \(M\).
  • Considering the order of age, an older and younger child, we compute all permutations - resulting in the set \( \{ FF, FM, MF, MM \} \).
Using combinatorics, we establish how many outcomes adhere to certain rules:
  • The subset \(A = \{FF\}\) signifies only female children.
  • The subset \(B = \{MM\}\) signifies only male children.
  • Subset \(C = \{FM, MF, MM\}\) includes at least one male.
Understanding and arranging these combinations allows us to easily track and predict outcomes in probability problems.
Mathematical Logic
Mathematical logic enables us to use reasoning to solve problems. In our exercise, logic helps us understand and manipulate sets to find intersections and unions of particular criteria.
  • Logical symbols and operations, such as "and" \((\cap)\), "or" \((\cup)\), "not" or complement \((\bar{B})\), structure our problem-solving approach.
  • For instance, finding \(C \cap \bar{B}\) requires determining elements common in both \(C\) and the complement of \(B\), which are \( \{FM, MF\}\).
Logical reasoning also supports us to avoid misinterpretations: understanding relationships between sets like having "at least one male" or "two males" clarifies the subsets we need.
Introducing concepts like intersection (commonality), union (combination), and complement (opposite) enriches our problem-solving toolkit in probability and beyond.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

If \(A\) and \(B\) are events and \(B \subset A,\) why is it "obvious" that \(P(B) \leq P(A) ?\)

Five firms, \(F_{1}, F_{2}, \ldots, F_{5},\) each offer bids on three separate contracts, \(C_{1}, C_{2},\) and \(C_{3} .\) Any one firm will be awarded at most one contract. The contracts are quite different, so an assignment of \(C_{1}\) to \(F_{1},\) say, is to be distinguished from an assignment of \(C_{2}\) to \(F_{1}\). a. How many sample points are there altogether in this experiment involving assignment of contracts to the firms? (No need to list them all.) b. Under the assumption of equally likely sample points, find the probability that \(F_{3}\) is awarded a contract.

The following game was played on a popular television show. The host showed a contestant three large curtains. Behind one of the curtains was a nice prize (maybe a new car) and behind the other two curtains were worthless prizes (duds). The contestant was asked to choose one curtain. If the curtains are identified by their prizes, they could be labeled \(G, D_{1},\) and \(D_{2}\) (Good Prize, Dud1, and Dud2). Thus, the sample space for the contestants choice is \(S=\left\\{G, D_{1}, D_{2}\right\\}\). a. If the contestant has no idea which curtains hide the various prizes and selects a curtain at random, assign reasonable probabilities to the simple events and calculate the probability that the contestant selects the curtain hiding the nice prize. b. Before showing the contestant what was behind the curtain initially chosen, the game show host would open one of the curtains and show the contestant one of the duds (he could always do this because he knew the curtain hiding the good prize). He then offered the contestant the option of changing from the curtain initially selected to the other remaining unopened curtain. Which strategy maximizes the contestant's probability of winning the good prize: stay with the initial choice or switch to the other curtain? In answering the following sequence of questions, you will discover that, perhaps surprisingly, this question can be answered by considering only the sample space above and using the probabilities that you assigned to answer part (a). i. If the contestant choses to stay with her initial choice, she wins the good prize if and only if she initially chose curtain \(G\). If she stays with her initial choice, what is the probability that she wins the good prize? ii. If the host shows her one of the duds and she switches to the other unopened curtain, what will be the result if she had initially selected \(G\) ? iii. Answer the question in part.(ii) if she had initially selected one of the duds. iv. If the contestant switches from her initial choice (as the result of being shown one of the duds), what is the probability that the contestant wins the good prize? v. Which strategy maximizes the contestant's probability of winning the good prize: stay with the initial choice or switch to the other curtain?

Suppose two dice are tossed and the numbers on the upper faces are observed. Let \(S\) denote the set of all possible pairs that can be observed. [These pairs can be listed, for example, by letting (2,3) denote that a 2 was observed on the first die and a 3 on the second.] a. Define the following subsets of \(S\) : A: The number on the second die is even. B: The sumof the two numbers is even. C: At least one number in the pair is odd. b. List the points in \(A, \bar{C}, A \cap B, A \cap \bar{B}, \bar{A} \cup B,\) and \(\bar{A} \cap C\)

A personnel director for a corporation has hired ten new engineers. If three (distinctly different) positions are open at a Cleveland plant, in how many ways can she fill the positions?

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.