Download Seventh Grade Glossary Sorted by Common Core Standards

Seventh Grade Glossary
Sorted by Common Core Standards Domain
The Number System
Absolute value - A number's distance from zero on a number line Ex. The absolute value of 2
is equal to the absolute value of -2.
Additive inverse - The opposite of a number . Ex: the additive inverse of 3 is –3. The sum of a
number and its additive inverse is zero.
Associative property - The sum or product of three or more numbers is the same, regardless of
how the numbers are paired Ex. a + (b + c) = (a + b) + c, a (b c) = (a b) c
Commutative property - The sum or product of two numbers is the same, regardless of the
order of the numbers. Ex. a + b = b + a, a b = b a
Distributive property - When one of the factors of a product is written as a sum or difference,
multiplying each addend first does not change the original product.
Ex. 3 (4 + 5) = (3 4) + (3 5)
Dividend - the number to be divided in a division problem.
Divisor - the number you are dividing by in a division problem.
Horizontal number line - A horizontal line representing the set of all real numbers. The number
line is typically marked showing integer values.
Identity property of One - the property that states that the product of one and any number is
that number.
Identity property of Zero - the property that states that the sum of zero and any number is that
number.
Identity property for addition - If you add zero to a number, the sum is the same as that given
number. Ex. 8 + 0 = 8 and a + 0 = a
Identity property for subtraction - If you add zero to a number, the sum is the same as that
given number. Ex. 8 - 0 = 8 and a - 0 = a
Integers - The set of whole numbers and their opposites {…-2, -1, 0, 1, 2…}
Inverse property - The result of two real numbers that combined will give the identity elements
of zero or one
Irrational number - Real numbers that cannot be expressed in the form a/b (a fraction) where a
and b are integers
Non zero divisor - a divisor that is not equal to zero
Opposite - two numbers that are equal distance from zero on a number line; also see additive
inverse
Quantity - an indefinite amount or number
Quotient - The result of division of one quantity by another (dividend/divisor = quotient)
Rational number - Any number that can be written in the form a/b where a is any integer and b
is any integer except zero
Repeating decimals - A decimal in which one or more numbers repeat indefinitely.
Terminating decimals - A decimal which ends or terminates.
Vertical number line - A vertical line representing the set of all real numbers. The number line
is typically marked showing integer values.
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Expressions and Equations
Coefficient - The numerical factor when a term has a variable (Ex. In the expression 3x + 2y =
16, 2 and 3 are coefficients.)
Conversion - a change in the units or form of a number or expression: the conversion of miles to
kilometers involves multiplying by 1.61
Equation - A statement that two mathematical expressions are equal
Ex. 5 + 3 = 8 and x + 7 = 15 are equations.
Estimation - A close rather than an exact answer
Expand - To multiply out the parts of an expression. Distributing is the opposite of factoring
Expression - A mathematical statement that does not contain an equal sign
Factor - One of two or more numbers that are multiplied together to get a product
(13 and 4 are both factors of 52 because 13 4 = 52.)
Linear expression - a combination of terms where the power of the highest variable is 1
Reasonableness - not expecting more than is possible: not expecting or demanding more than is
possible or achievable
Variable - A symbol such as a letter, box, star, etc. that is used to represent an unknown or
undetermined value in an expression or number sentence (equation)
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Statistics and Probability
Box plots - Organization of data in a graph that shows the minimum, first quartile, median, third
quartile, and maximum values (The graph uses a rectangle (or box) to represent the middle 50%
of the date (interquartile range) and line segments (or whiskers) at both ends to represent the
remainder of the data.)
Certain - Sure to happen; having a probability of 1.
Chance - the possibility of a particular outcome in an uncertain situation; also: the DEGREE of
likelihood of such an outcome
Compound events - An event consisting of two or more non-mutually exclusive events
Convenience sample - A convenience sample is a sample where the participants are selected, in
part or in whole, based on the convenience of the researcher (i.e., availability or accessibility).
Data - Information gathered by observation, questioning, or measurement
Discrepancy - the quality or state of disagreeing or being at variance
Equally likely outcomes - outcomes which have the same probability
Estimate - An answer that is close to the exact answer and is found by rounding or other
methods; to find such an answer
Event - an outcome or set of outcomes of an experiment or situation
Experimental probability - A statement of probability based on the results of a series of trials
Experimental probability (event) = number of trials resulting in a favorable outcome
Total number of trials in experiment
Frequency - the number of times each value occurs
Geometric probability - A probability determined by comparing the area of a given section to
that of a total available region.
Impossible - can never happen; having a probability of 0.
Interquartile range (IQR) - The difference between the upper quartile and the lower quartile
Likely - an event that is probably not going to occur in a sample
Maximum - The greatest value of the function if it has such an extreme value
Mean - The sum of a set of numbers divided by the number of elements in the set (also referred
to as average)
Mean absolute deviation (MAD) - In statistics, the absolute deviation of an element of a data
set is the absolute difference between that element and a given point. Typically the point from
which the deviation is measured is a measure of central tendency, most often the median or
sometimes the mean of the data set.
The Mean Absolute Deviation is calculated in three simple steps.
1) Determine the Mean: Add all numbers and divide by the count
2) Determine deviation of each variable from the Mean
3) Make the deviation 'absolute' by squaring and determining the roots i.e. eliminate the
negative aspect
Measure of variability - A descriptive statistic describing the spread or dispersion of data.
Median - The middle number (or the average of the two middle numbers, when necessary) in a
set of numbers that are arranged from least to greatest
Minimum - The greatest value of the function if it has such an extreme value
Mode - The number that occurs most often in a set of data (there may be one, more that one, or
no mode)
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Statistics and Probability continued
Organized list - a list of numbers or items which are categorized
Outcome - The results of an event (Heads and tails are the two outcomes of the event of
tossing a coin.)
Population - An entire group of objects or individuals considered for a survey.
Predication - A future event foretold by using a trend formed from the collected historical data.
Probability - A number from zero to one that indicates the likelihood that something (an event)
will happen (The closer a probability is to one, the more likely it is that an event will happen.)
Probability compound event - An event whose probability of occurrence depends upon the
probability of occurrence of two or more independent events. An event that consists of two or
more events that is not mutually exclusive.
Probability model - A probability model, also known as a stochastic model, is a mathematical
formulation that incorporates an element of randomness
Quartile - The quartiles divide an ordered set of data into four groups of the same size
Random sample - A sample in which each individual or object in the entire population has an
equal chance of being selected.
Range - The difference between the maximum and minimum in a set of data
Relative frequency - The ratio of the number of occurrences of a given type of event or the
number of members of a population in a given class to the total number of events or the total
number of members of the population.
Sample - part of the population
Sample space - all possible outcomes of an experiment
Simulation - a model of an experience, often one that would be too difficult or too time
consuming to actually perform
Simulation - the mathematical representation of the interaction of real world objects
Statistics - The branch of mathematics that deals with the collection, organization, analysis and
interpretation of numerical data.
Survey response - A list of questions and answers that a group of people are asked in order to
determine the characteristics of a group.
Table - A display of data, usually arranged in rows and columns
Theoretical probability - Identifying, using mathematical expectations, the number of possible
ways an event can happen compared to all of the possible events
Tree diagrams - a branching diagram that shows all possible combinations or outcomes of an
event
Unlikely - an event that is probably not going to occur in a sample
Variation - the variance is a measure of how far a set of numbers is spread out. It is one of
several descriptors of a probability distribution, describing how far the numbers lie from the
mean (expected value).
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Geometry
Actual length - a verifiable measure of a distance
Acute triangle - a triangle with three acute angles
Adjacent angles - Two angles that have a common side and a common vertex and whose
interiors do not overlap
Alternate exterior angles - A pair of angles formed when a third line (a transversal) crosses two
other lines (These angles are on opposite sides of the transversal and are inside the other two
lines.)
Alternate interior angles - A pair of angles formed when a third line (a transversal) crosses two
other lines (These angles are on opposite sides of the transversal and are outside the other two
lines.)
Angles - Two non-collinear rays having the same vertex
Area - The amount of space in square units
Circumference - The distance around a circle or the maximum distance around a sphere
Complementary angles - Two angles that have measures with a sum of 90
Concave - A polygon with one or more diagonals that have points outside of the polygon
Congruent - ( ) Having exactly the same size and shape Ex. If you put one figure on top of the
other, they would match exactly.
Convex - A polygon with all interior angles measuring less than 180 (No segment that
connects two vertices can be drawn outside of the polygon.)
Corresponding angles - Two angles that lie on the same side of the transversal, in
corresponding positions with respect to the two lines that the transversal intersects (The angles
are congruent if the two lines are parallel.)
Cube - A polyhedron with six square faces
Diameter - A line segment that passes through the center of the circle and has endpoints on the
circle (chord)
Equilateral triangle - A triangle in which all have sides are the same length
Inspection - A method of solving a problem by looking at evidence to support a claim or theory.
Interior angles - The inside angle of a polygon formed by two adjacent sides
Irregular - A polygon with at least two non-congruent sides or angles
Isosceles triangle - A triangle that has at least two congruent sides
Lateral face - The word "lateral" denotes the side of a three-dimensional figure, as opposed to
the base.
Lines - A straight path that extends infinitely in opposite directions
Obtuse triangle - a triangle with an obtuse angle
Parallel lines - Lines that are the same distance apart and never meet
Perpendicular lines - Two rays, lines, or line segments that form right angles
Pi - The ratio of the circumference of a circle to its diameter (Pi is the same for every circle,
approximately 3.14)
Plane figure - A figure that can be entirely contained in a single plane
Polygon - A closed two-dimensional figure made up of segments called sides, which intersect
only at their endpoints called vertices
Prism - A polyhedron with two parallel faces (called bases) that are the same size and shape
Proportion - An equation a/b = c/d that states that the two ratios are equivalent
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Geometry continued
Pyramid - A polyhedron in which one faces (the base) is a polygon and the other faces are
formed by triangles with a common vertex (the apex) (A pyramid is classified according to the
shape of its base.)
Quadrilateral - A polygon with four sides
Radius - A line segment from the center of a circle or sphere to any point on the circle or sphere
(also, the length of such a line segment)
Ratios - Comparisons of two quantities with like units. Ratios can be expressed with fractions,
decimals, percents, or words. They can be written with a colon between the two numbers being
compared.
Rays - A part of a line that has one endpoint and extends endlessly in one direction
Regular - A polygon for which all sides are congruent and all angles are congruent.
Right prism - A prism which has bases aligned one directly above the other and has lateral faces
that are rectangles.
Right triangle - A triangle which has a right (90°) interior angle.
Scale drawing - Pictures that show relative sizes of real objects
Scalene triangle - triangle for which all three sides have different lengths.
Sides - Any of the line segments that make up a polygon
Similar figures - Figures that are exactly the same shape, but not necessarily the same size
Slicing - to cut an object either vertically or horizontal
Sum of interior angles - The sum of the measures of the interior angles of a convex polygon
with n sides is (n-2)180
Examples:
Triangle or (‘3-gon’) sum of interior angles: (3-2) 180 = 180°
Quadrilateral which has four sides (‘4-gon') sum of interior angles: (4-2)180 = 360°
Hexagon which has six sides (‘6-gon') sum of interior angles: (6-2)180 = 720°
Supplementary angles - Two angles whose measures total 180 degrees
Surface area - The total area of the faces (including the bases) and curved surfaces of a threedimensional figure
Three dimensional solids (figures) - A geometric figure that has three dimensions: length,
width and height.
Triangle - a three sided figure
Two dimensional figures - a plane figure with two dimensions - length and width
Vertical angles - When two lines intersect, the angles that do not share a common side; the
angles opposite each other. Vertical angles have equal measures.
Volume - A measure of the amount of space occupied by a three-dimensional shape, generally
expressed in “cubic” units
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Ratios and Proportional Relationships
Commission - A fee paid to a person for making a sale.
Complex fraction - fraction which has, as part of its numerator and/or denominator, at least one
other fraction.
Constant of proportionality - a constant ratio of two variables related proportionally
Dependent variable - In a function, a variable whose value is determined by the value of the
related independent variable
Equivalent ratio - ratios which name the same comparison
Gratuity - tip for services given; usually given as a percent
Independent variable - In a function, a variable that determines the value of the related
dependent variable
Markdowns - the amount by which an original price is reduced
Markups - the amount by which an original price is increased
Percent decrease - A percent change describing a decrease in a quantity
Percent error - or approximation error in some data is the discrepancy between an exact value
and some approximation to it. An approximation error can occur because the measurement of the
data is not precise (due to the instruments), or approximations are used instead of the real data
(e.g., 3.14 instead of π).
Percent increase - A percent change describing an increase in a quantity
Proportional relationships - Having the same or a constant ratio.
Ratio - Comparisons of two quantities with like units (Ratios can be expressed with fractions,
decimals, percents, or words. They can be written with a colon between the two numbers being
compared.)
Sales tax - A percent of the cost of an item. This is charged by the government to raise money
Simple interest - A fixed percent of the principal
Unit rate - A rate in which the second quantity in the comparison is one unit
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