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Exercises Numbers, fractions and percents

Example 4.57 from Prealgebra, 4.4 Add and Subtract Fractions with Common Denominators

Add and Subtract Fractions with Common Denominators: example 4.57

Find the sum: $- \frac{3}{12} + (- \frac{5}{12}) .$

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

$- \frac{3}{12} + (- \frac{5}{12})$

Add the numerators and place the sum over the common denominator. $\frac{−3 + (−5)}{12}$

Add. $\frac{−8}{12}$

Simplify the fraction. $- \frac{2}{3}$

Your turn

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

Find each sum: $- \frac{4}{15} + (- \frac{6}{15}) .$

How did it go?

PreviousAdd and Subtract Fractions with Common Denominators: example 4.56 Next Add and Subtract Fractions with Common Denominators: example 4.58

From Prealgebra (1st edition) by OpenStax (Rice University), section 4.4, 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.