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80 terms

acute triangle

A triangle that contains only angles that are less than 90 degrees.

area

the measure of how many square units it takes to cover a two-dimensional shape exactly

array

an arrangement of objects in rows and columns

bar graph

the use of bars of different lengths to display data

capacity/volume

the measure of how much a container can hold when it is full

certain

describes an event that will always occur

commutative property

the order of the addends in addition or the factors in multiplication does not change the sum or product

composite number

a number that has more than two factors

congruent

having the same shape and size

customary units

units used in the measurement of capacity (cups, pints, quarts, gallons), length (inches, feet, yards, miles), and weight (ounces, pounds, tons)

decimal

a number with one or more digits to the right of the decimal point

decimal point

a period used in decimal numbers to separate the whole number from the part that shows tenths, hundredths, etc...

edge

a line segment where two faces meet

equation

a number sentence with an equal sign

equilateral triangle

a triangle with three equal sides

equivalent fractions

fractions that name the same amount;example 1/3 and 2/6

estimate

round numbers where an exact answer is not necessary

expanded form (notation)

a way to write numbers by showing the value of each digit

face

a flat surface of a three-dimensional object

fact family

a group of related facts that use the same numbers

factors

numbers that can divide another number evenly

favorable outcome

the outcome you are looking for in an experiment

fraction

a number that names part of a whole or part of a group

front-end estimation

estimating by using only the value of the digit that is farthest to the left of the number

impossible

when an event will never occur

inequality

a number sentence that uses the symbols greater than and less than

intersecting lines

lines that go through the same point

isosceles triangle

a triangle with two equal sides

likely

describes an event that will happen more than half the time

line

a straight path of points that goes on forever in two directions (arrow on each end)

line graph

a graph that shows how data changes over time

line plot

organization of data by showing it along a number line

line segment

a part of a line that has two endpoints

median

the middle number in a set of data arranged in numerical order (least to greatest)

mixed number

a number that has both a whole number and a fraction

mode

the number that occurs the most often in a set of data

multiple

the product of a given whole number and another number

numerator

the top number in a fraction that tells how many parts of a whole or group are being named

obtuse triangle

a triangle that contains an angle of more than 90 degrees

ordered pairs

numbers used to find the location of a point on a coordinate grid

parallel lines

lines that are always the same distance apart

parallelogram

a quadrilateral in which opposite sides are parallel and of equal length

perimeter

the measure of the edge all the way around a two-dimensional shape

perpendicular lines

lines that intersect to form four right angles

place-value chart

a chart that shows the places and the place values of the digits in a number

plane

a flat surface extending without end in all directions

point

a location in space

prime number

a number that has exactly two factors, the number itself and 1

probability

a way of describing how likely it is that an event will happen

quadrilateral

a polygon that has four sides and four vertices

quotient

the answer in a division problem

range

the difference between the greatest number and the least number in a set of data

rectangle

a quadrilateral with four right angles and two pairs of parallel sides

reflection

the movement of a figure by flipping it over a line creating a mirror image

regroup

the renaming of a number such as 10 ones regrouped as 1 ten and 0 ones, to assist in addition or subtraction (borrowing and carrying)

related facts

facts that are in the same fact family

remainder

the amount left over when a whole number cannot be divided evenly

rhombus

a quadrilateral with four sides of equal length in which opposite sides are parallel

right triangle

a triangle that includes a right angle

rotation

turning a figure around a point

rotational symmetry

when a figure can be rotated onto itself after a rotation of less than a complete circle

round

a way to estimate a number to the nearest ten, hundred, and so on

scale

numbers on the side or bottom of a graph that tells what each bar or point stands for

scalene triangle

a triangle with side measures of three different lengths

square

a quadrilateral with four equal sides and four right angles

standard form

a number written with one digit for each place value

survey

a way to collect data by asking questions and recording answers

three-dimensional

objects that take up space

translation

the movement of a figure by sliding it

trapezoid

a quadrilateral with one pair of parallel sides

two-dimensional

flat figures that are sometimes called plane figures

unlikely

describes an event that will happen less than half the time

variable

a letter or symbol that represents an unknown number

Venn diagram

a graph that uses overlapping circles to represent how data groups are alike or different

vertex (plural vertices)

a point where three or more edges meet

volume

the number of cubic units that will fit into a three-dimensional object

denominator

the bottom number of a fraction telling how many parts a whole is divided into

a fraction smaller than one

the numerator is less than the denominator

a fraction equal to a whole

the numerator and denominator are equal

improper fraction

the numerator is greater than the denominator - a fraction greater than a whole