Practice Quiz: Subsets of Real Numbers

What is the smallest category in the real number system?

• Natural numbers

• Whole numbers

• Integers

• Rational numbers

Classify -5.

• -5 is classified as a Whole number and Natural number.

• -5 is classified as an Integer and Rational number.

• -5 is classified as a Fraction and Irrational number.

• -5 is classified as a Real number and Imaginary number.

Give an example of a Rational Number.

• 3/4

• √2

• π

• -5

Give an example of an Irrational Number.

• 3.14

• √2

• π (pi)

• 7

What are Integers?

• Whole numbers that can be positive, negative, or zero (-2, -1, 0, 1, 2, ...)

• Only positive whole numbers

• Only negative whole numbers

• Decimal numbers that are not whole

What are Rational Numbers?

• Numbers that can be expressed as a fraction of two integers (e.g., 1/2, 3, -4)

• Numbers that cannot be expressed as a fraction

• Whole numbers only

• Numbers that are always positive

What are Natural Numbers?

• The set of all integers including negative numbers (-1, -2, -3, ...)

• The set of positive integers starting from 1 (1, 2, 3, ...)

• The set of all rational numbers (fractions)

• The set of real numbers including decimals and fractions

What are Irrational Numbers?

• Numbers that can be expressed as a fraction of two integers (e.g., 1/2, 3/4)

• Numbers that cannot be expressed as a fraction of two integers (e.g., √2, π)

• Whole numbers that are not prime (e.g., 4, 6, 8)

• Numbers that can be expressed as a repeating decimal (e.g., 1/3, 0.666...)

True or False: Integers do not contain decimals or fractions, but rational numbers do.

• True

• False

• Only integers contain decimals

• Only rational numbers contain fractions

Can a number be both an Integer and a Rational Number?

• Yes, all integers are also rational numbers because they can be expressed as a fraction with a denominator of 1.

• No, integers cannot be expressed as fractions.

• Only positive integers are rational numbers.

• All rational numbers are integers.