Chapter 2 Math Vocab 7th Grade Pre Algebra

Term Definition
Base When a number is written in exponential form, the number that is used as a factor.
(Example: 5^4 (5 is the base) which equals 5x5x5x5.)
Composite Number A whole number greater than 1 with more than two factors. (Example: 24 is a composite number that has 1,2,3,4,6,8,12,and 24 as factors.)
Divisible A number is this term by a second whole number if the first number can be divided by the second number with a remainder of 0. (Example: 16 is divisible by 1,2,4,8,and 16.
Exponent Tells how many times a number, or base, is used as a factor. (Example: 3^4 (4 is the exponent) equals 3x3x3x3.
Factor A whole number that divides another whole number with a remainder of 0. (Example: 1,2,3,46,12,18,and 36 are factors of 36.)
Formula A rule that shows the relationship between two or more quantities. (Example: The formula p=2L+2W gives the perimeter of a rectangle in terms of its length and width.
Greatest Common Factor (GCF) This term of two or more numbers is the greatest number that is a factor of all of the numbers. (Example: The GCF of 12 and 30 is 6.)
Least Common Denominator (LCD) This term of two or more fractions is the least common multiple of their denominators. (Example: The LCD of fractions 3/8 and 7/10 is 40.
Least Common Multiple (LCM) This term of two numbers is the smallest number that is a multiple of both numbers. (Example: The LCM of 15 and 6 is 30.)
Multiplicative Inverse The reciprocal of a number is called this term. (Example: The multiplicative inverse of 4/9 is 9/4.
Power A number that can be expressed using a base and exponent. (Example: 3^4,5^2, and 2^10 are powers.
Prime Factorization Writing a composite number as the product of its prime factors is the prime factorization of the number. (Example: The prime factorization of 12 is 2x2x3, or 2^2×3.)
Prime Number A whole number with exactly two factors, 1 and itself. (Example: 13 is a prime number because its only factors are 1 and 13.)
Rational Number Any number written as a quotient of two integers where the denominator is not 0. (Example: 1/3,-5,6.4,0.666…,-2 4/5,0, and 7/3 are rational numbers.
Reciprocals Two numbers are this term if their product is 1. (Example: The numbers 4/9 and 9/4 are reciprocals.
Relatively Prime A fraction a/b is in simplest form when a and b are relatively prime, which means they only have 1 as a common factor. (Example: 9/10, 1/4, and 2/3 are examples of this term.)
Repeating Decimal A decimal that repeats the same digits without end. The repeating block can contain one digit or more than one digit. (Example: 0.888…=0.8 with the repeating sign over 8.
Scientific Notation A number is in scientific notation if the first factor is greater than or equal to 1 and less than 10, and the second factor is a power of 10. (Example: 37,000,000 is written as 3.7×10^7 in this term.
Terminating Decimal A decimal that stops. (Example: Both 0.6 and 0.7265 are this term.)