Number Classification

Question 1

Whole Numbers

Answer 1

{0, 1, 2, 3, 4, …}

The set of all positive integers and zero.

Question 2

Natural Numbers

Answer 2

{1, 2, 3, 4, …}

The set of all positive integers.

Question 3

Integers

Answer 3

{…, -3, -2, -1, 0, 1, 2, 3, …}

The set of all numbers that do not contain any decimal or fractional value.

Question 4

Non-positive Numbers

Answer 4

{…, -4, -3, -2, -1, 0}

The set of all negative integers.

Question 5

Even Numbers

Answer 5

A number is even if there is no remainder when it is divided by 2.

Question 6

Prime Numbers

Answer 6

A prime number is any number that can only be evenly divided by two unique numbers: itself and 1.

eg: 2, 3, 5, 7, 11

1 is not a prime number because both values must be unique.

Question 7

Rational Numbers

Answer 7

A number that can be expressed in fractional form without approximation.

Decimal values must either be terminating or repeating.

Question 8

Composite Numbers

Answer 8

Numbers that are divisible by more than themselves and 1.

Question 9

Irrational Numbers

Answer 9

Any number that cannot be expressed by a fraction without approximation. The decimal is an infinite, non-terminating, non-repeating value.