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Exercises Expressions, exponents and radicals

Example 7.1 from Prealgebra, 7.1 Rational and Irrational Numbers

Rational and Irrational Numbers: example 7.1

Write each as the ratio of two integers: ⓐ $−15$ ⓑ $6.81$ ⓒ $−3 \frac{6}{7} .$

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution

ⓐ

$−15$

Write the integer as a fraction with denominator 1. $\frac{−15}{1}$

ⓑ

$6.81$

Write the decimal as a mixed number. $6 \frac{81}{100}$

Then convert it to an improper fraction. $\frac{681}{100}$

ⓒ

$−3 \frac{6}{7}$

Convert the mixed number to an improper fraction. $- \frac{27}{7}$

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Write each as the ratio of two integers: ⓐ $−24$ ⓑ $3.57 .$

How did it go?

PreviousPrime Factorization and the Least Common Multiple: example 2.54 Next Rational and Irrational Numbers: example 7.2

From Prealgebra (1st edition) by OpenStax (Rice University), section 7.1, licensed under CC BY 4.0. Original at openstax.org. We split the solution into steps; the words, numbers and figures are the book's. OpenStax doesn't endorse this site.