Question

To which subset of the real numbers does the number 2.18 belong?

a) Natural numbers
b) Rational numbers
c) Irrational numbers
d) Whole numbers

Answer 1

The number 2.18 belongs to the subset of real numbers known as rational numbers, as it can be expressed as the quotient of two integers. The answer is b) Rational numbers.

Step-by-step explanation:

The number 2.18 belongs to the subset of real numbers known as rational numbers. Rational numbers are those that can be expressed as the quotient or fraction of two integers, where the denominator is not zero. In the case of 2.18, it can be written as the fraction
`\( (218)/(100) \)` or simplified to
`\( (109)/(50) \)`, where both the numerator and denominator are integers.

Natural numbers (Option a) include positive integers starting from 1, but 2.18 is not a natural number. Whole numbers (Option d) include natural numbers and zero, but 2.18 is not a whole number. Irrational numbers (Option c) cannot be expressed as a fraction of two integers, but 2.18 is rational. Therefore, the correct subset is rational numbers (Option b).