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Exercises Numbers, fractions and percents

Example 4.85 from Prealgebra, 4.6 Add and Subtract Mixed Numbers

Add and Subtract Mixed Numbers: example 4.85

Add by converting the mixed numbers to improper fractions: $3 \frac{7}{8} + 4 \frac{3}{8} .$

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

$3 \frac{7}{8} + 4 \frac{3}{8}$

Convert to improper fractions. $\frac{31}{8} + \frac{35}{8}$

Add the fractions. $\frac{31 + 35}{8}$

Simplify the numerator. $\frac{66}{8}$

Rewrite as a mixed number. $8 \frac{2}{8}$

Simplify the fraction. $8 \frac{1}{4}$

Since the problem was given in mixed number form, we will write the sum as a mixed number.

Your turn

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

Find the sum by converting the mixed numbers to improper fractions:

$5 \frac{5}{9} + 3 \frac{7}{9} .$

How did it go?

PreviousAdd and Subtract Mixed Numbers: example 4.84 Next Add and Subtract Mixed Numbers: example 4.86

From Prealgebra (1st edition) by OpenStax (Rice University), section 4.6, 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.