Everyday Mathematics Parent Handbook

Glossary for Everyday Mathematics

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endpoint (2) a) The point at either end of a line segment. Endpoints are used to name line segments. b) The point at the end of a ray. Example: Segment TL or segment LT names a line segment between and including points T and L.
equidistant marks (1) Marks equally distant from one to the next along a line segment. equilateral triangle (3) A triangle in which all three sides are the same length. equivalent fractions (3) Fractions that have different numerators and denominators but name the same number. Example: and are equivalent fractions. equivalent names (1) Different ways of naming the same number. Example: 2 + 6, 4 + 4, 12 - 4, 18 - 10, 100 - 92, 5 + 1 + 2, eight, VIII, and |||| ||| are some of the names for 8. estimate (1) A calculation of a close, rather than exact, answer; a "ballpark" answer; a number close to another number. even number (1) A whole number such as 2, 4, 6, and so on that can be evenly divided by 2 (divided by 2 with 0 remainder). exponential notation (4) A shorthand way of representing repeated multiplication of the same number. In the example below the small raised 3, called the exponent, indicates how many times the number 2, called the base, is used as a factor. Example: 23 is exponential notation for 2 x 2 x 2. extended fact (3) A number sentence obtained by multiplying numbers in a basic fact by 10, 100, and so on. Knowing 5 + 8 = 13 makes it easy to find 50 + 80; knowing 6 x 7 = 42 makes it easy to find 6 x 70.
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face (1) A flat surface on a 3-dimensional shape. fact (basic fact) (1) Any of the simple number sentences that are the basis of all computation. The basic addition facts are 0 + 0 = 0 through 10 + 10 = 20; the basic subtraction facts are 0 - 0 = 0 through 20 - 10 = 10; the basic multiplication facts are 0 x 0 = 0 through 10 x 10 = 100; the basic division facts are 0 ÷ 1 = 0 through 100 ÷ 10 = 10. Turn-around facts are pairs of related facts such as 3 x 5 = 15 and 5 x 3 = 15. fact family (1) A group of addition or multiplication facts together with the related subtraction or division facts. Example: 5 + 6 = 11, 6 + 5 = 11, 11 – 5 = 6, and 11 – 6 = 5 form a fact family; 5 x 7 = 35, 7 x 5 = 35, = 5, and = 7 form a fact family.
fact triangle (1) Triangular card labeled with the numbers of a fact family for practice with addition/subtraction and multiplication/ division facts. The two one-digit numbers and their sum or product (marked with an asterisk) appear in the corners of the triangle.
factor (verb) (2) To factor a given number is to find the values that multiple together to give you the original number. Example: Factor 24 Possible answers: 6 x 4 = 24 3 x 8 = 24 1 x 24 = 24 2 x 3 x 4 = 24 factor (noun) (2) Any numbers that are multiplied together. Factors may be whole numbers, fractions, or decimals. Example: 4, 3, and 2 are factors in 4 x 3 x 2 = 24; 0.5 and 25 are factors in 0.5 x 25 = 12.5; and 9 are factors in x 9 = 4 ; and -2 and -5 are factors in - 2 x (-5) = 10. factor pair (4) Two factors of a number n whose product is the number n. A number may have more than one factor pair. Example: The factor pairs of 21 are 1 and 21 and 3 and 7.
factor rainbow (4) A way of showing factor pairs in a list of all the factors of a number. This can be helpful in checking whether a list of factors is correct.
factor string (4) When a number is named by at least two factors. In the example, the factor string has three factors, so its length is 3. The number 1 may not be used in a factor string. Example: A factor string for the number 24 is 2 x 3 x 4. Fahrenheit (1) The temperature scale in which 32 degrees is the temperature at which water freezes; 212° is the temperature at which it boils. fair (4) A coin or die is said to be fair if, over a large number of tosses, the results are consistent with the predictions of probability. Heads and tails should come up about equally often; the six sides of a die should come up equally often. foot (ft) (1) In the U.S. customary system, a unit of length equivalent to 12 inches or of a yard. formula (4) A general rule for finding the value of something. A formula is often written in abbreviated form with letters called variables. Example: A formula for distance traveled can be written as d = r * t, where the variable d stands for distance, r for speed, and t for time. fraction (1) A number in the form or a/b, where a and b are whole numbers and b is not 0. Fractions are used to name part of a whole object, part of a whole collection of objects, to compare two quantities, or as the quotient of a divided by b.
Frames and Arrows (1) Diagrams to represent number sequences—sets of numbers ordered according to a rule. The dia-grams consist of frames in which num-bers are written and arrows that apply the rules for moving from one frame to another.
frequency (2) The number of times an event or value occurs in a set of data.
frieze pattern (4) A design made by repeating one or more shapes along a strip by reflections, rotations, and or translations (slides).
fulcrum (1) The center support of a pan balance or other lever.
function machine (1) A diagram of an imaginary machine programmed to process numbers according to a certain rule. A number is input into the machine and is transformed into a second number (output) through the application of a rule.
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