The mean, also known as the average, is a measure of central tendency that represents the sum of a set of numbers divided by the number of elements in the set. It is commonly used to describe the typical value of a set of numbers.

To calculate the mean of a set of numbers, you add up all the numbers and then divide by the total number of values. The formula for calculating the mean is:

Mean (μ) = (Sum of all values) / (Number of values)

Let's calculate the mean for the following set of numbers: 5, 8, 12, 15, 20.

Mean (μ) = (5 + 8 + 12 + 15 + 20) / 5

Mean (μ) = 60 / 5

Mean (μ) = 12

- Understand the concept of mean as a measure of central tendency.
- Learn the formula for calculating the mean: Mean (μ) = (Sum of all values) / (Number of values).
- Practice calculating the mean for different sets of numbers.
- Understand how outliers can affect the mean.
- Learn how to interpret the mean in the context of a given data set.

Remember that the mean is just one way to describe the central tendency of a set of numbers, and it's important to consider other measures of central tendency, such as the median and mode, to fully understand the distribution of the data.

Study GuideSimilarity and scale Worksheet/Answer key

Similarity and scale Worksheet/Answer key

Similarity and scale Worksheet/Answer key

Similarity and scale Worksheet/Answer keyUsing Similar Polygons Worksheet/Answer keySimilar Polygons Worksheet/Answer keyUsing Similar Polygons Worksheet/Answer keySimilar Polygons

Number and Operations (NCTM)

Understand numbers, ways of representing numbers, relationships among numbers, and number systems.

Understand and use ratios and proportions to represent quantitative relationships.

Compute fluently and make reasonable estimates.

Develop, analyze, and explain methods for solving problems involving proportions, such as scaling and finding equivalent ratios.

Geometry (NCTM)

Analyze characteristics and properties of two- and three-dimensional geometric shapes and develop mathematical arguments about geometric relationships.

Understand relationships among the angles, side lengths, perimeters, areas, and volumes of similar objects.

Create and critique inductive and deductive arguments concerning geometric ideas and relationships, such as congruence, similarity, and the Pythagorean relationship.

Apply transformations and use symmetry to analyze mathematical situations.

Describe sizes, positions, and orientations of shapes under informal transformations such as flips, turns, slides, and scaling.

Measurement (NCTM)

Apply appropriate techniques, tools, and formulas to determine measurements.

Solve problems involving scale factors, using ratio and proportion.

Grade 8 Curriculum Focal Points (NCTM)

Geometry and Measurement: Analyzing two- and three-dimensional space and figures by using distance and angle

Students use fundamental facts about distance and angles to describe and analyze figures and situations in two- and three-dimensional space and to solve problems, including those with multiple steps. They prove that particular configurations of lines give rise to similar triangles because of the congruent angles created when a transversal cuts parallel lines. Students apply this reasoning about similar triangles to solve a variety of problems, including those that ask them to find heights and distances. They use facts about the angles that are created when a transversal cuts parallel lines to explain why the sum of the measures of the angles in a triangle is 180 degrees, and they apply this fact about triangles to find unknown measures of angles. Students explain why the Pythagorean Theorem is valid by using a variety of methods - for example, by decomposing a square in two different ways. They apply the Pythagorean Theorem to find distances between points in the Cartesian coordinate plane to measure lengths and analyze polygons and polyhedra.