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

Key Concepts in Engineering Economics

Engineering Economics is the science dealing with quantitative analysis techniques for selecting the most preferable alternative from several technically viable options.

Fundamental Principles

Four fundamental principles must be applied in all engineering economic decisions:

• The time value of money
• Differential (or incremental) cost and revenue
• Marginal cost and revenue
• The trade-off between risk and reward

Core Terminology Explained

Ethics

A set of principles that guides a decision-maker in distinguishing between right and wrong.

Market Interest Rate

The interest rate quoted by financial institutions, which refers to the cost of money for borrowers or the earnings from money for lenders.

Interest Rate

The cost, or price,

Inheritance Tax Base Reductions

We highlight three primary types of base reductions:

Kinship-Based Reductions

The amount of reduction varies depending on the heir's kinship group. There are four standard groups:

• Group I: Descendants under 21 years old.
• Group II: Descendants aged 21 and older, ascendants, and the spouse.
• Group III: Second and third-degree collateral relatives by affinity.
• Group IV: Fourth-degree or more distant collateral relatives, and strangers.

Life Insurance Reductions

If the beneficiary is a spouse, ascendant, or descendant, a 100% reduction applies, up to a maximum limit.

Primary Residence Reductions

If the heir is a spouse, descendant, or ascendant and inherits the primary residence, a 95% reduction applies, up to a specific ceiling.... Continue reading "Understanding Inheritance Tax: Reductions, Rates, and Coefficients" »

Measures of Central Tendency:

Arithmetic Mean

Used for:

Intervals and pooled data (xi = class mark)

Data are not grouped (tables).

Data are grouped (tables) but no intervals.

Median

The middle value in a sorted dataset.

For an odd number of observations, it's the middle number.

Sort data from lowest to highest before finding the median.

Mode

The value that appears most frequently in a dataset.

Mid-Range

RM = (Maximum Value + Minimum Value) / 2

Geometric Mean

G = ⁿ√(x₁ * x₂ * ... * xn)

Harmonic Mean

H = n / ( (1/x₁) + (1/x₂) + ... + (1/xn) )

Quadratic Mean (Root Mean Square)

Q = √[ (x₁² + x₂² + ... + xn²) / n ]

Percentile

A measure indicating the value below which a given percentage of observations in a group falls.

Kth Percentile

Measures of... Continue reading "Statistical Measures: Central Tendency, Dispersion, and Form" »

The Book of Compensation: A Payroll Record

"The Book of Compensation" is a crucial record where all amounts related to employee compensation payments are documented. This includes Social Security contributions, legal deductions, and agreed taxes.

Payroll Components: Understanding Salary Calculations

Employee salaries are comprised of three main calculation types:

• Taxable Income
• Non-Taxable Income
• Discounts/Deductions

Taxable Income Components

Taxable income includes elements such as basic salary, overtime, bonuses, gratuities, and commissions. These are considered taxable because their total amount is subject to estimated discount rates and pension laws.

Base Salary

The base salary is the fixed monetary amount paid for regular periods. By law, these... Continue reading "Employee Compensation Structure: Payroll and Benefits Explained" »

Quadratic Forms and Symmetric Matrices

The quadratic form is defined as w(x) = x^TAx, where M(w)_c = 1/2(A + A^T) is the associated symmetric matrix in the canonical basis.

Change of basis formula: M(w)_b = (P_BC)^T · M(w)_c · P_BC.

Rank properties: rg(w) = rg(A) = rg(M(w)_c). If rg(w) = max, the form is non-degenerate; otherwise, it is degenerate.

Diagonalization of Symmetric Matrices

For a symmetric matrix A, applying elementary row and column operations leads to (D | P^T), where D is diagonal. The goal is to obtain zeros in the off-diagonal positions.

A form w admits a non-degenerate orthonormal basis if the rank is maximum or the diagonal elements of D are non-zero.

Signature and Sylvester's Criterion

The signature sig(w) = sig(A) = (p, r_p), where rg(w)

Valuation Criteria

Historical Cost

For Assets: The purchase price or production cost. This includes the amount of cash paid or payable, plus the fair value of any other consideration given for the acquisition. All costs directly related to the acquisition and necessary to bring the asset to operating condition are included.

For Liabilities: The value corresponding to the consideration received in exchange for incurring the debt. In some cases, it is the amount of cash expected to be paid to settle the liability in the ordinary course of business.

Fair Value

The price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between knowledgeable, willing market participants at the measurement date. It is determined... Continue reading "Understanding Asset and Liability Valuation Concepts" »

1. Payment Process Methods

Payment methods can be categorized as follows:

• 1) Cash: Includes physical cash income deposited into the supplier's account, bank transfers, Cheques, debit cards, and credit cards.
• 2) Deferred: Includes financial instruments like the Bill of Exchange and the Promissory Note.

2. The Receipt Document

A receipt is a document issued by the person who collects the money and delivered to the payer as proof of payment for acquired goods or services provided. Receipts must be printed, typically using numbered receipt books (with a matrix or stub). The person paying must be given their receipt, while the matrix (stub) is held by the issuer to justify the payment.

3. The Cheque (Check)

A cheque is a document issued against a bank... Continue reading "Financial Instruments: Cheques, Bills, Notes, and Cards" »

Precision Measurement Techniques and Instruments

Action

This is the procedure of comparing a magnitude, known as drive power, with another of the same nature to find the relation between them.

Magnitude

Everything is likely to be measured, such as length, mass, or time.

Metrology

The science that studies the measurement of magnitudes. It is currently attempting to standardize so that it will be unique for everyone, and called the International System of Units (SI).

Accuracy of Measurement

Accuracy of measurement is determined by its degree of approximation to the actual value of the magnitude or conventional that is measured. Accuracy is the ability of a measuring instrument to give results with very high accuracy.

Weighing

1. A) Direct measurement: We

Working Papers

These are the documents in which the auditor records the data and information obtained during their review, as well as the results of the tests performed.

Summary Warrant

A sample of major accounts that are an item.

Worksheet

This is the card that shows the groups or items that comprise the financial statements.

Decree of Detail

The items that comprise an account balance of a major account or any other account.

Certificates of Verification

The work performed to verify the correctness of an item or transaction.

Situations for Audit Work Plan

• Ensure that the service is clearly controlled.
• Be fully aware of what is being offered.

Conditions to Perform the Audit

• Maintain independence of mind regarding the specific client.
• Possess the ability to

Saw-Tooth Diagram for Inventory Management

The Saw-Tooth Diagram is a design used for input control and monitoring of stock. This graph serves to manage inventories, ordering, and the volume of flow itself.

The optimal quantity is determined according to the purchase price, storage costs, and handling volume. The optimal lot (often related to the Economic Order Quantity or EOQ, here referred to as PDID) includes the purchase price, carrying costs, PDID costs, overhead costs, and costs incurred until the item reaches the point of sale or placement.

Henry Gantt and the Gantt Chart

Henry Gantt was an American engineer belonging to the classical school of organization who planned American military transport during World War I, using bar-line graphs.... Continue reading "Project Scheduling Diagrams: Gantt, CPM, PERT, and Inventory Control" »