## Algebra 1: Common Core (15th Edition)

$-\frac{1}{12}$
Convert all the fractions to like fractions with the least common denominator of 12. To find the difference of like fractions, subtract the numerators and retain the common denominator. $1−\frac{1}{2}−\frac{1}{3}−\frac{1}{4}$⟶ change the denominator of each fraction to 12 $=1−\frac{1\times6}{2\times6}−\frac{1\times4}{3\times4}−\frac{1\times3}{4\times3}$⟶ simplify $=1−\frac{6}{12}−\frac{4}{12}−\frac{3}{12}$⟶ subtract each term working left to right $=\frac{6}{12}−\frac{4}{12}−\frac{3}{12}$ $=\frac{2}{12}−\frac{3}{12}$ $=−\frac{1}{12}$