Chapter 0.2, Problem 12E

To determine

To find: The set or sets of numbers to which real number $-\frac{72}{8}$ belong.

Answer to Problem 12E

The real number $-\frac{72}{8}$ is an integer and a rational number.

Explanation of Solution

Given information:

The real number $-\frac{72}{8}$ .

Formula used:

Real numbers are categorized as follows:

Natural number are the positive numbers (integer) which start from 1.

Whole number are positive numbers which start from 0.

Integers are numbers which is not a fraction (whole number).

Rational numbers are number which are in the form of $\frac{p}{q}$ where p and q are integers, $q\ne 0$ .

Irrational numbers are those number which cannot be expressed in the form of $\frac{p}{q}$ where $q\ne 0$ .

Calculation:

Consider the providedreal number $-\frac{72}{8}$ .

Rewrite it as,

  $\begin{array}{c}-\frac{72}{8}=-\frac{8\times 9}{8}\\ =-9\\ =-\frac{9}{1}\end{array}$

Recall that real numbers are categorized as follows:

Natural number are the positive numbers (integer) which start from 1.

Therefore, it is not a natural number.

Whole number are positive numbers which start from 0.

Therefore, it is not a whole number.

Integers are numbers which is not a fraction (whole number).

Therefore it is an integer.

Rational numbers are number which are in the form of $\frac{p}{q}$ where p and q are integers, $q\ne 0$ .

Therefore, it is a rational number.

Irrational numbers are those number which cannot be expressed in the form of $\frac{p}{q}$ where $q\ne 0$ .

Therefore, it is not an irrational number.

Thus, the real number $-\frac{72}{8}$ is an integer and a rational number.