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Exercises Numbers, fractions and percents

Example 4.78 from Prealgebra, 4.5 Add and Subtract Fractions with Different Denominators

Add and Subtract Fractions with Different Denominators: example 4.78

Evaluate $y - \frac{5}{6}$ when $y = - \frac{2}{3} .$

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
We substitute $- \frac{2}{3}$ for $y$ in the expression.

$y - \frac{5}{6}$

Rewrite as equivalent fractions with the LCD, 6. $- \frac{4}{6} - \frac{5}{6}$

Subtract. $- \frac{9}{6}$

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

Your turn

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

Evaluate: $y - \frac{1}{2}$ when $y = - \frac{1}{4} .$

How did it go?

PreviousAdd and Subtract Fractions with Different Denominators: example 4.77 Next Add and Subtract Fractions with Different Denominators: example 4.79

From Prealgebra (1st edition) by OpenStax (Rice University), section 4.5, 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.