PA Vocabulary Real Number System

Front

Irrational numbers

Back

Numbers that cannot be expressed as a ratio of two integers. Their decimal expansions are nonending and nonrepeating. Denoted by I.

Front

Rational numbers

Back

The set of numbers that can be expressed as a fraction, where a and b are integers and b ≠ 0. Denoted by the symbol Q.

Front

Integers

Back

The set of counting (natural numbers), their opposites, and zero {...-3, -2, -1, 0, 1, 2, 3...}. Denoted by the symbol Z.

Front

Whole numbers

Back

The set of counting (natural) numbers and zero {0, 1, 2, 3...} Denoted by W.

Front

Counting (natural) numbers

Back

The set of positive numbers that begins at one {1, 2, 3...} Denoted by N.

Front

Repeating Decimal

Back

A decimal with one or more digits that repeats endlessly (e.g., 0.666..., 0.727272..., 0.08333...).

Front

Terminating Decimal

Back

A decimal that stops.

Front

Place value

Back

The value of a digit as determined by its location in a number such as ones, tens, hundreds, one thousands, ten thousands, etc.

Front

Decimal notation

Back

A representation of a real number, not including counting (natural) numbers, which uses a decimal point to show place values that are less than one, such as tenths and hundredths (0.25, 9.85, 0.023, etc.).

Front

Order numbers

Back

To arrange a set of numbers based on their numerical value.