Real Numbers

Algebra 1

Real Number System

All rational and irrational numbers

Natural Numbers

The positive integers (whole numbers) 1, 2, 3 etc., and sometimes zero as well.

Whole numbers

A number without fractions; an integer.

Integers

A number that is not a fraction; a whole number.

Rational numbers

Decimal expansion either terminates after a finite number of digits (example: ¾ = 0.75), or eventually begins to repeat the same finite sequence of digits over and over (example: 9/44 = 0.20454545…)

Decimal

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

Terminating decimal

A decimal number that ends or terminates.

Repeating decimal

A decimal that repeats a digit or group of digits forever.

Irrational numbers

Any real number (positive or negative number, or 0) that cannot be written as a fraction.

Numerator

The top number in a fraction.

Denominator

The bottom number in a fraction.