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 Pre-algebra Arithmetics Integers Divisibility Decimals Fractions Exponents Percentages Proportional reasoning Radical expressions Graphs Algebra Monomials Polynomials Factoring Linear Equations Graphs of linear equations Rectangular Coordinate System Midpoint Formula Definition of Slope Positive and negative slope Determine the slope of a line Equations of lines Equation of lines (from graph) Applications of linear equations Inequalities Quadratic equations Graphs of quadratic equations Absolute Value Radical expressions Exponential equations Logarithmic equations System of equations Graphs and functions Plotting points and naming quadrants Interpreting Graphs Relations and Functions Function Notation Writing a Linear Equation from a Table Writing a Linear Equation to describe a Graph Direct Variation Indirect Variation Domain and range Sequences and series Matrices Inverse of a matrix Determinants Inner product Geometry Triangles Polygons 2-D Shapes 3-D Shapes Areas Volume Pythagorean Theorem Angles Building Blocks Geometry Transformations Parallel, coincident and intersepting lines Distances in the plane Lines in space Plane in space Angles in the space Distances in the space Similarity Precalculus Sequences and series Graphs Graphs Definition of slope Positive or negative slope Determine the slope of a line Equation of a line (slope-intercept form) Equation of a line (point slope form) Equation of a line from graph Domain and range Quadratic function Limits (approaches a constant) Limits (approaches infinity) Asymptotes Continuity and discontinuities Parallel, coincident and intersepting lines Introduction to Functions Limits Continuity Asymptotes Trigonometry Trigonometric ratios The reciprocal trigonometric ratios Trigonometric ratios of related angles Trigonometric identities Solving right angles Law of sines Law of cosines Domain of trigonometric functions Statistics Mean Median Mode Quartiles Deciles Percentiles Mean deviation Variance Standard Deviation Coefficient of variation Skewness kurtosis Frequency distribution Graphing statistics & Data Factorial Variations without repetition Variations with repetition Permutations without repetition Permutation with repetition Circular permutation Binomial coefficient Combinations without repetition Combinations with repetition

 Previous concepts Frequency distribution Ungrouped data Grouped data Quiz
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Population or target population: A population consists of all elements -individuals, items, or objects- whose characteristics are being studied. The population that is being studied is also called target population.

Sample: A portion of the population selected for study.

Survey: The collection of information from the elements of a population or a sample.

Variable: A characteristic under study that assumes differents values for different elements.

Examples of variables are the incomes of households, the number of houses built in a city per month during the past year, the makes of cars owned by people,...

A variable may be classified as quantitative or qualitative:

Qualitative or non-numeric: Data are called qualitative or non-numeric if they can not be written down as numbers.

The status of an undergraduate college student is a qualitative variable because a student can fall into any one of four categories: freshman, sophomore, junior, or senior.

Quantitative or numeric: Data are called quantitative or numeric if they can be written down as numbers

Quantitative measurements divide further into two types:

• Discrete variable: A variable whose values are countable. In other words, a discrete variable can assume only certain values with no intermediate values.

• The number of cars sold in any day at a car dealership is a discrete variable because the number of cars sold must be 0,1,2,3,... and we can count it. The number of cars sold cannot be between 0 and 1, or between 1 and 2,...

• Continuous variable: A variable that can assume any numerical value over a certain interval or intervals.

• The time taken to complete an examination is an example of continuous variable because it can assume any value, let us say, between 30 and 60 minutes.