Lecture Notes: AIT's Version 7 Math Portion Exam Prep
Fractions
- Numerator: Number above the fraction line; represents parts of the whole.
- Example: In ( \frac{3}{4} ), 3 is the numerator.
- Denominator: Number below the fraction line; represents how many equal parts the whole is divided into.
- Example: In ( \frac{3}{4} ), 4 is the denominator.
- Equivalent Fractions: Different fractions representing the same value once simplified.
- Example: ( \frac{2}{8} = \frac{1}{4} ) by dividing both numerator and denominator by 2.
Place Values and Decimals
- Basic Place Values: Ones, tens, hundreds, and thousands.
- Example: In 1,234:
- 4 is in the ones place.
- 3 in the tens place represents 30.
- 2 in the hundreds place represents 200.
- 1 in the thousands place represents 1,000.
- Decimals: Extend to the right of the decimal point.
- Example: 0.2 as ( \frac{2}{10} ).
Percentages
- Definition: Represents parts per hundred.
- Example: 90% means 90 out of 100.
- Conversion to Fractions and Decimals:
- Percent to fraction: Simplify ( \frac{90}{100} = \frac{9}{10} ).
- Percent to decimal: Move decimal two places left (e.g., 25% = 0.25).
Order of Operations (PEMDAS)
- Sequence: Parentheses, Exponents, Multiplication, Division, Addition, Subtraction.
- Example: Solve (4 + (3 \times 2) - (8 / 2)).
- Perform operations within parentheses first, then move left to right through multiplication/division, and addition/subtraction.
Rational and Irrational Numbers
- Rational Numbers: Can be expressed as a fraction of two integers.
- Example: 3.75 as ( \frac{375}{100} ).
- Irrational Numbers: Cannot be expressed as a simple fraction.
- Examples: ( \pi, e, \sqrt{2} ).
Comparing Rational Numbers
- Methods: Use number lines or stacking to order from least to greatest.
- Inequalities: Use symbols (<, >, =) to compare values.
Algebra Basics
- Expressions: Terms, coefficients, variables, and constants.
- Example: In (15x + 5), 15 is the coefficient, x is the variable, and 5 is the constant.
- Solving Equations: Use inverse operations to isolate variables.
- Proportions: Cross-multiply to solve.
Estimation and Measurement
- Length, Weight, Capacity: Use metric system conversions.
- Example: 1 meter approx. height of a doorknob.
Word Problems
- Translate words into algebraic expressions.
- Example: "Six more than a number" as (x + 6).
Graphical Representation
- Types: Cartesian coordinates, scatter plots, line, pie/circle, and bar graphs.
- Use Cases: Choose appropriate graph type based on data.
Statistical Measures
- Mean: Average of a data set.
- Median: Middle number when data is ordered.
- Mode: Most frequently occurring number.
- Range: Difference between highest and lowest numbers.
Probability
- Basic Concept: Total number of favorable outcomes divided by total possible outcomes.
- Example: Probability of rolling a 3 on a die is ( \frac{1}{6} ).
Review of Important Formulas
- Area and Volume Formulas
- Rectangle Area: ( length \times width ).
- Triangle Area: ( \frac{1}{2} \times base \times height ).
- Circle Circumference: ( \pi \times diameter ).
- Circle Area: ( \pi \times radius^2 ).
- Volume for Prisms: ( base_area \times height ).
These notes outline key concepts and methods needed to prepare for the AIT's version 7 math exam, including conversion methods, equation solving, statistical analysis, and graph interpretation.