Notes, summaries, assignments, exams, and problems for Mathematics

Faculty and Student Responses

A university president proposed that all students must take a course in ethics as a requirement for graduation. The table below gives the responses of a sample of faculty and students at the university when asked their opinion on this issue.

Y: FAVOR O: Oppose N: Neutral

Totals

F: Faculty         45             15             10                    70

S: Student        90             110             30                  ₂₃₀ 

 Totals   135               125                40

Probabilities

1. Find the following probabilities; each time ONE person is being randomly selected.

P(S or Y) = (230 + 135 – 90)/... Continue reading "Calculating Probabilities from a Table: Ethics Course Requirement" »

Systematic Sampling: Type of Probability Sampling Method

In systematic sampling, sample members from a larger population are selected according to a random starting point but with a fixed, periodic interval. The sampling interval, calculated by dividing the population size by the desired sample size, determines the selection.

Oversampling: Techniques to Adjust Class Distribution

Oversampling is a data analysis technique used to adjust the class distribution of a data set, ensuring a balanced representation of different classes/categories.

P Value: Probability of Obtaining Extreme Test Results

The p value represents the probability of obtaining test results at least as extreme as the observed results during the test, assuming the null hypothesis... Continue reading "Understanding Systematic Sampling and Statistical Significance" »

Worksheet: Revisiting Calculating Probabilities from a Table

1. Goals

P(F) = 251/478 = 0.525

The probability that a randomly selected student is a girl is 0.525.

P(P^C) = (247 + 90)/478 = (478 – 141)/478 = 337/478 = 0.705

The probability that a randomly selected student did not indicate being popular as a primary goal is 0.705.

P(B or S) = (227 + 90 – 60)/478 = 257/478 = 0.538

The probability that a randomly selected student is a boy or indicated a primary goal is to excel at sports or both is 0.538.

P(B and S) = 60/478 = 0.126

The probability that a randomly selected student is a boy and indicated a primary goal is to excel at sports is 0.126.

P(S|B) = 60/227 =... Continue reading "Calculating Probabilities from a Table" »

Operating Segments & Disclosures

Revenue Test Criteria

Both external and intersegment revenue are included in the revenue test.

Profit & Loss (P&L) Test

The P&L test includes 10% of the higher absolute value of intersegment revenue and expenses.

Management's Business Evaluation

Management evaluates business results along product, customer, or geographic lines, not based on legal entity results.

Defining an Operating Segment

• Includes state
• Reviewed by the chief decision maker
• Discrete information available
• Product is the primary breakdown, with geographic and customer as secondary.

Operating Segment Disclosure Rules

• Must reconcile to GAAP.
• For immaterial operating segments, revenue, P&L, and assets must be disclosed.

Non-Operating Segment

In the examples C = {1,2,3,4} and D = {3,4,5}

SymbolMeaningExample{ }Set: a collection of elements{1,2,3,4}A ∪ BUnion: in A or B (or both)C ∪ D = {1,2,3,4,5}A ∩ BIntersection: in both A and BC ∩ D = {3,4}A ⊆ BSubset: A has some (or all) elements of B{3,4,5} ⊆ DA ⊂ BProper Subset: A has some elements of B{3,5} ⊂ DA ⊄ BNot a Subset: A is not a subset of B{1,6} ⊄ CA ⊇ BSuperset: A has same elements as B, or more{1,2,3} ⊇ {1,2,3}A ⊃ BProper Superset: A has B's elements and more{1,2,3,4} ⊃ {1,2,3}A ⊅ BNot a Superset: A is not a superset of B{1,2,6} ⊅ {1,9}A^cComplement: elements not in AD^c = {1,2,6,7}
When  = {1,2,3,4,5,6,7}A − BDifference: in A but not in B{1,2,3,4} − {3,4} =

Unit 7: Scheduling and Time Management

• Date: A numbered day in a month. *What's the date today?
• Schedule: To plan your tasks. *We have to schedule the flight.
• Paper Diary: A traditional notebook to write down tasks and important dates. *I use the diary more than the electronic planner.
• Electronic Planner: A digital device used to store information.
• Wall Calendar: A paper display showing 12 months divided into weeks and days. *I have to erase an appointment on the wall calendar.
• Up to Date: Containing the latest information. *I bought a diary to stay up to date.
• Appointment: A formal arrangement to meet or visit.
• Erase: To remove something. *I have to erase an appointment on the wall calendar.
• Deadline: A specific time or day by which something must

Understanding Prefixes and Suffixes

A prefix is a letter or a group of letters that appears at the beginning of a word and changes the word’s original meaning.

A suffix is a letter or a group of letters that is usually added onto the end of words to change the way a word fits into a sentence grammatically.

Nouns, verbs, adjectives, and adverbs all tend to use different suffixes, which makes them easier to remember. Collectively, prefixes and suffixes are known as affixes.

What Are Affixes?

An affix is added to the root of a word to change its meaning.

• An affix added to the front of a word is known as a prefix.
• One added to the back is known as a suffix.

Sometimes, prefixes are hyphenated. Read more about hyphens in prefixes.

Examples of Affixes

Here... Continue reading "Understanding Prefixes, Suffixes, and Root Words" »

Inventory Costing Methods: Situational Analysis

For each of the following situations, determine whether FIFO, LIFO, or Weighted Average would apply:

• FIFO would produce the highest amount of net income in an inflationary environment.
• FIFO would produce the highest amount of assets in an inflationary environment.
• FIFO would produce the lowest amount of net income in a deflationary environment.
• Weighted Average would produce the same unit cost for assets and cost of goods sold in an inflationary environment.
• LIFO would produce the lowest amount of net income in an inflationary environment.
• Weighted Average would produce an asset value that was the same regardless of whether the environment was inflationary or deflationary.
• LIFO would produce the lowest