Real-World Algebraic Problems • Explore • Lenny.com

Solving Continuously Compounded Interest Problems with the PERT Formula

This math tutorial provides a clear, step-by-step guide on how to solve word problems involving continuously compounded interest. The video introduces the continuous compound interest formula, A = Pe^rt (often referred to as the "PERT" formula), and explains the significance of each variable: the future value (A), principal investment (P), Euler's number (e), interest rate (r), and time (t). Through two distinct examples, the narrator demonstrates how to calculate the future value of an investment and how to determine the time required for an investment to double in value. Key mathematical themes include exponential growth functions, algebraic manipulation of formulas, and the application of natural logarithms (ln) to solve for unknown variables in an exponent. The video carefully walks through the algebraic steps required to isolate the time variable 't' by taking the natural log of both sides, reinforcing the inverse relationship between exponential and logarithmic functions. Additionally, the video introduces the "Rule of 72," a mental math shortcut for estimating doubling time, and compares this approximation with the precise calculated result. This video is highly valuable for high school Algebra II, Pre-Calculus, and Financial Math classrooms. It bridges the gap between abstract algebraic concepts—like the number 'e' and logarithms—and practical financial literacy. Teachers can use this resource to scaffold lessons on exponential modeling, demonstrate the utility of logarithms in real-world scenarios, or introduce students to basic investment planning and the power of compound interest over time.

The Organic Chemistry Tutor

5mins 32s

How to Solve Percent Word Problems Using Equations

This math tutorial by "Math with Mr. J" provides a clear, step-by-step demonstration of how to solve real-world percent problems using the percent equation (percent x whole = part). The video specifically tackles a word problem that asks students to determine what percentage of a high school's total student body is comprised of seniors. It walks viewers through the entire process: identifying the known and unknown variables, calculating the total population to find the "whole," setting up the algebraic equation, and performing the necessary inverse operations to solve for the missing percentage. The video explores key mathematical themes including algebraic reasoning, variable isolation, and data interpretation from lists. It emphasizes the importance of understanding the relationship between the "part," the "whole," and the "percent." Additionally, it covers practical arithmetic skills such as summing multiple values to find a total, performing division to isolate a variable, converting a decimal result into a percentage by moving the decimal point, and rounding to the nearest whole number. For educators, this video serves as an excellent instructional tool or review resource for units on ratios, proportional reasoning, and percentages. Its visual approach—using a digital chalkboard and color-coded text—helps students focus on the structure of the equation. Teachers can use this video to model how to extract relevant information from word problems (like realizing the "whole" must be calculated by adding up all class sizes) and to reinforce the procedure for converting decimals to percentages in a meaningful context.

Math with Mr. J

4mins 56s

How to Solve Square-Root Equations

This instructional video provides a comprehensive guide to solving square-root equations, specifically focusing on advanced problems that result in quadratic equations. Hosted by a narrator named Randy, the lesson breaks down a complex algebraic procedure into four distinct, manageable steps: isolating the square-root expression, squaring both sides to eliminate the radical, solving for the unknown variable, and checking for extraneous solutions. The video uses a digital whiteboard format where calculations are written out in real-time alongside clear typography explaining the steps.

Miacademy & MiaPrep Learning Channel

10mins 31s

Interpreting Percent Rate of Change in Exponential Models

This instructional video guides students through the process of interpreting exponential models to determine percent rates of change. The presenter, Randy, breaks down two real-world scenarios—a ball's decreasing velocity and a tree's increasing branch count—to demonstrate how to extract growth and decay rates directly from exponential equations. By constructing tables of values and analyzing the mathematical patterns, the video demystifies the relationship between the base of an exponent and the percentage change it represents. The video explores key themes of exponential functions, specifically distinguishing between exponential growth and decay. It focuses heavily on understanding the base of the exponent as a factor and how it relates to the number 1 (representing 100%). Concepts covered include function notation, evaluating exponents, converting decimals to percentages, and interpreting mathematical models in practical contexts. For educators, this resource is an excellent tool for bridging the gap between abstract algebraic formulas and concrete understanding. It addresses the common student confusion between the decay factor (what remains) and the decay rate (what is lost). The step-by-step derivation of the "shortcut" method empowers students to quickly analyze equations without needing to perform repetitive calculations, making it valuable for Algebra I and Algebra II curriculums.

Miacademy & MiaPrep Learning Channel

8mins 55s

Understanding Angles in Parallel Lines and Transversals

This educational video provides a comprehensive lesson on the geometric relationships created when a transversal line intersects two parallel lines. Building on prior knowledge of general transversals, the instructor guides students through identifying special angle pairs—such as alternate interior, alternate exterior, corresponding, and consecutive interior angles—and understanding their specific properties of congruence or supplementarity. The video uses visual animations to demonstrate why these relationships exist, showing how the intersections are identical when lines are parallel. The content covers key geometric theorems and applies them to solving mathematical problems. Students learn to determine unknown angle measurements by identifying relationships like vertical angles and linear pairs alongside the new parallel line theorems. The lesson progresses from basic arithmetic applications to more complex algebraic problems where students must set up and solve equations to find variables representing angle measures. This resource is highly valuable for geometry classrooms as it visualizes abstract concepts through color-coding and animations, making the "why" behind the theorems clear. It offers a structured approach to learning, starting with conceptual understanding, moving to theorem definitions, and concluding with guided practice problems. The integration of algebra also helps reinforce cross-disciplinary math skills, making it an excellent tool for standard instruction or review.

Miacademy & MiaPrep Learning Channel

12mins 1s

Solving Real-World Problems Using Average Rate of Change

This video provides a clear and practical guide to solving word problems involving average rate of change. It bridges the gap between abstract mathematical concepts and real-world scenarios by demonstrating that while real-life functions (like hiking speeds or fuel consumption) are rarely perfectly linear, the average rate of change allows us to calculate a single, useful rate over a specific interval. The narrator, Justin, walks viewers through three distinct examples: a distance-time graph, a fuel consumption graph, and a data table relating temperature to campground attendance. Key themes include identifying input and output variables, interpreting graphs of non-linear functions, understanding positive versus negative slopes in context, and calculating slope using the "rise over run" formula. The video specifically emphasizes how to handle fractional answers in word problems, teaching students to interpret them meaningfully (e.g., "2 campers for every 3 degrees" rather than "0.66 campers"). It also reinforces the difference between instantaneous speed at a single moment and average speed over a duration. For educators, this resource is excellent for Algebra I or II classes transitioning from linear equations to general functions. It serves as a vital conceptual building block for calculus by introducing the idea of secant lines. The clear visuals and step-by-step calculations make it an ideal tool for direct instruction, review, or as a flipped classroom assignment to help students grasp why slope formulas are relevant beyond straight lines.

Miacademy & MiaPrep Learning Channel

4mins 40s

Solving Real-World Problems Using Linear Equations

In this comprehensive math tutorial, Justin guides students through the process of applying linear equations to solve real-world word problems. As the final video in a unit on linear equations, it synthesizes knowledge of different equation forms—point-slope, standard, and slope-intercept—demonstrating how to select the best tool for specific scenarios. The video features an animated robot character and clear, step-by-step visual breakdowns of the algebra involved. The video explores three distinct problem types: tracking technology adoption trends using point-slope form, calculating ticket prices for a school fundraiser using standard form, and budgeting for travel luggage using slope-intercept form. A key theme is 'translation'—converting English sentences into mathematical variables, slopes, and points. It also touches on the critical skill of interpreting mathematical results in real-world contexts, such as recognizing when decimal answers must be rounded down for discrete objects like suitcases. For educators, this resource is invaluable for bridging the gap between abstract algebraic manipulation and practical application. It explicitly models the thinking process required to deconstruct a word problem, identify knowns and unknowns, and set up an equation. The video is particularly useful for teaching students how to distinguish between rate of change (slope) and initial values (y-intercepts) in narrative text, and how to handle constraints where mathematical solutions might need logical adjustment to fit reality.

Miacademy & MiaPrep Learning Channel

5mins 50s

Modeling Financial Growth and Decay with Exponential Functions

This video connects abstract algebraic concepts to real-world financial literacy by exploring how exponential functions model money. It specifically focuses on constructing equations in the form y = a(b)^x to represent scenarios involving compound interest and depreciation. Through a step-by-step analysis, the presenter, Justin, guides viewers through setting up equations, defining variables, and interpreting the results to make predictions about future value. The lesson addresses key themes such as the difference between growth and decay in financial contexts. A significant portion of the video is dedicated to debugging common student misconceptions, such as using the percentage rate directly as the base of the exponent. By testing these incorrect assumptions with input-output tables, the video visually demonstrates why the growth factor must be calculated as (1 + r) for growth and (1 - r) for decay, providing a deep conceptual understanding of the mathematics involved. For educators, this resource serves as an excellent bridge between theoretical algebra and practical application. It encourages critical thinking by asking students to predict outcomes and verify equations using logic and tables. The video culminates in a comprehensive word problem about a college savings account, providing a model for solving multi-step application problems that students will encounter in standard Algebra curricula.

Miacademy & MiaPrep Learning Channel

14mins 21s

How to Use Arithmetic Sequence Formulas and Calculate Partial Sums

This educational video provides a comprehensive tutorial on the fundamental formulas associated with arithmetic sequences and series. The narrator begins by defining an arithmetic sequence as a list of numbers with a common difference and demonstrates how to identify patterns using specific examples. The video methodically breaks down the notation used in algebra, distinguishing between term position (n) and term value (a_n), and explains the concept of a common difference (d). The core of the video focuses on deriving and applying essential algebraic formulas. It introduces the standard nth term formula, explores variations that allow calculation from any starting term (not just the first), and explains the concept of the arithmetic mean (the average of terms). The latter part of the video shifts to arithmetic series, explaining the difference between sequences and series, and teaching how to calculate partial sums using both long-hand addition and the summation formula. This resource is highly valuable for high school algebra and pre-calculus classrooms. It clarifies common points of confusion, such as the difference between a term's value and the sum of a series up to that term. The step-by-step problem-solving approach makes it an excellent tool for introducing new concepts or reviewing for exams. Teachers can use this video to scaffold learning, moving from basic pattern recognition to complex summation notation (sigma).

The Organic Chemistry Tutor

15mins 3s

Understanding Similar Polygons and Finding Unknown Values

This educational video provides a comprehensive introduction to the concept of similar polygons in geometry. It breaks down the two fundamental requirements for similarity: corresponding angles must be congruent, and corresponding sides must be proportional. The instructor, Justin, guides viewers through visual examples using quadrilaterals, pentagons, and triangles to demonstrate how to identify these attributes and verify similarity using both scale factors and ratios. The video covers essential skills such as writing similarity statements, identifying corresponding parts even when figures are rotated or re-oriented, and calculating scale factors between figures. It emphasizes the importance of consistency when setting up ratios (e.g., always going from Figure A to Figure B) and offers practical tips like redrawing figures to share the same orientation to avoid errors. For classroom application, this video serves as an excellent instructional tool for connecting geometric concepts with algebraic problem-solving. It concludes with step-by-step walkthroughs of two practice problems: one focusing on finding missing angles and calculating ratios, and another that requires setting up a proportion to solve for an unknown variable (x) in a side length expression. This dual focus makes it valuable for reinforcing both geometry standards and algebraic manipulation skills.

Miacademy & MiaPrep Learning Channel

9mins 53s

Mastering Trigonometric Ratios and SOH CAH TOA

This comprehensive mathematics tutorial introduces the fundamental concepts of trigonometric ratios within right-angled triangles. The video systematically explains the definitions of sine, cosine, and tangent using the mnemonic device SOH CAH TOA, demonstrating how to identify the opposite, adjacent, and hypotenuse sides relative to a specific angle. Through clear, hand-drawn examples on a blackboard style interface, the narrator guides viewers from basic ratio identification to more complex applications involving special right triangles and inverse functions. The content covers several key topics including calculating ratios for standard triangles (like 8-15-17 and 3-4-5), determining exact trigonometric values for special angles (30, 45, and 60 degrees), and summarizing these values in a reference table. The video progresses to practical problem-solving techniques, showing students how to use algebra to find missing side lengths when given an angle and one side, as well as how to use inverse trigonometric functions (specifically arctan) to calculate missing angles when given two sides. Ideally suited for high school geometry and trigonometry classes, this video serves as both an introduction and a practice resource. The narrator frequently encourages active learning by prompting viewers to pause the video and attempt problems before seeing the solution. This format allows teachers to use the video as an interactive classroom tool for direct instruction, guided practice, or independent review, effectively addressing common student difficulties in setting up and solving trigonometric equations.

The Organic Chemistry Tutor

17mins 52s

Applying Domain Restrictions to Real-World Problems

This video bridges the gap between abstract mathematical concepts and real-life application by exploring domain restrictions through everyday scenarios. Hosted by Justin, the lesson moves beyond theoretical definitions to demonstrate how physical reality imposes natural limits on mathematical functions. The video specifically examines three distinct situations—rolling a die, pricing old smartphones, and buying groceries—to illustrate how context determines valid input values. The content covers key algebraic concepts including input/output relationships, discrete versus continuous functions, and inequality notation. It guides viewers through the logical process of determining a domain, starting with a mathematical assumption and then refining it based on reality (e.g., recognizing that time and money cannot be negative). The distinction between discrete data (countable integers like die rolls) and continuous intervals (time and currency) is visually represented using set notation and number lines. For educators, this video is an excellent tool for scaffolding the difficult concept of domain and range in word problems. It addresses the common student struggle of translating text into mathematical notation and provides a clear model for error analysis—specifically showing why a mathematically correct inequality might be practically incorrect without real-world context. This resource helps students develop the critical thinking habits necessary for modeling with mathematics.

Miacademy & MiaPrep Learning Channel

3mins 45s

Lessons

Algebra Bridge Part 2

Carlos Arenas

Algebra Bridge Part 1

Carlos Arenas

Foundation Missions

Elsa LaLone

The Career Summit

Elsa LaLone

Brevet Express

Enseignante

Clutter Busters

Erin Venuti

Absolute Value Basics

Kianna Ferrante

Function Blueprint

Mary Roche

Sabermetrics Showdown

Karen Dhuyvetter

Wave Riders

Aysenur Ersoy

Math Foundations Roadmap

Kara Francis

Schoolyard Math Detectives

caitlynn.meadows

Materials

Launch Pad Focus Companion

Carlos Arenas

Part Two Answer Key

Carlos Arenas

Escape Challenge Workbook

Carlos Arenas

Algebra Preview Workbook

Carlos Arenas

Statistics Probability Workbook

Carlos Arenas

Geometry Foundations Workbook

Carlos Arenas

Linear Scout Workbook

Carlos Arenas

Pattern Pilot Workbook

Carlos Arenas

Launch Pad Answer Key

Carlos Arenas

Proportional Patrol Workbook

Carlos Arenas

Equation Sentinel Workbook

Carlos Arenas

Expression Force Workbook

Carlos Arenas

Sequences

Algebra 1 Launch Pad

Carlos Arenas

Math in Motion: The 2-Hour Summit

Elsa LaLone

Algebra 1 Launch Pad

Cheyenne Watkins

Shark Capital

djaenecke

Regents Mastery Suite

Kayla Borozny

Regents Blueprint Mastery

Jessica Hiauw

Math Blueprints Sequence

Mr Whitfield

Shark Tank Math Ventures

djaenecke

Geometric Foundations

dbonicoro

Math Mastery Marathon

Michell Kisler

Math Blueprints Grade 5

Hope Joel

Chemical Equations Lab

Lorie.Shiveley

Videos

Solving Continuously Compounded Interest Problems with the PERT Formula

How to Solve Percent Word Problems Using Equations

How to Solve Square-Root Equations

Interpreting Percent Rate of Change in Exponential Models