Overview
This lecture walks through solving a full-length 22-question GED math practice test, covering key problem types like fractions, equations, percent problems, geometry, functions, and graph interpretation.
Fractions & Operations
- To divide fractions: keep the first, flip the second, change division to multiplication, then multiply across.
- Always simplify fractions after calculation.
Solving Equations & Inequalities
- Isolate variables by performing inverse operations.
- If an equation’s denominator equals zero, the expression is undefined.
- For inequalities, dividing by a negative flips the inequality sign.
Averages & Percents
- To find an average, sum all items and divide by the count.
- For percent problems, use the formula: part ÷ percent = whole.
Geometry: Surface Area, Circumference, Area, Perimeter
- Surface area of a sphere: use formula with radius (half the diameter).
- Circumference of a circle: use π × diameter if diameter is given.
- For prisms not on the formula sheet, sum the areas of all faces.
- Trapezoid area: (1/2) × height × (base1 + base2).
- Perimeter: add up all side lengths.
Slope & Graphs
- Get y alone for slope-intercept form (y = mx + b); m is the slope.
- Slope between two points: (rise) ÷ (run).
- For coordinates: move horizontally first, then vertically.
Functions & Expressions
- Substitute given values into functions to evaluate.
- For expressions: "product" means multiply, "less than" means subtract at end.
- Factoring: FOIL possible answers to check which matches the original.
Combinations & Probability
- Total combinations: multiply the number of choices for each item.
Word Problems & Practical Applications
- For cost/rate: find cost per unit then multiply by the total units needed.
- To find the greatest distance on a graph, find the highest y-value.
- Average speed = distance ÷ time.
Key Terms & Definitions
- Undefined — occurs when dividing by zero.
- Quotient — result of a division.
- Product — result of a multiplication.
- Slope (m) — rise/run; the rate of change of a line.
- Surface Area — total area covering the surface of a 3D shape.
- Circumference — distance around a circle.
- Perimeter — distance around a shape.
- FOIL — method for multiplying two binomials: First, Outer, Inner, Last.
Action Items / Next Steps
- Review and practice similar problems, focusing on key concepts and formulas discussed.
- Familiarize yourself with calculator functions for GED math.
- Ensure you know how to use the GED formula sheet for geometry problems.