## Basic College Mathematics (9th Edition)

$\frac{7}{8}$
$\frac{1}{5}$ + $\frac{3}{10}$ + $\frac{3}{8}$ The least common multiple of 5, 10 and 8 is 40, so first rewrite the fractions as like fractions with a denominator of 40. This is the least common denominator (LCD) of 5,10 and 8. Step 1 $\frac{1}{5}$ = $\frac{}{40}$ Divide 40 by 5, getting 8, multiply numerator and denominator by 8 $\frac{1}{5}$ = $\frac{1 * 8}{5 * 8}$ = $\frac{8}{40}$ $\frac{3}{10}$ = $\frac{}{40}$ Divide 40 by 10, getting 4, multiply numerator and denominator by 4 $\frac{3}{10}$ = $\frac{3 * 4}{10 * 4}$ = $\frac{12}{40}$ $\frac{3}{8}$ = $\frac{}{40}$ Divide 40 by 8, getting 5, multiply numerator and denominator by 5 $\frac{3}{8}$ = $\frac{3 * 5}{8 * 5}$ = $\frac{15}{40}$ Now, add the like fractions Step 2 : $\frac{8}{40}$ + $\frac{12}{40}$ + $\frac{15}{40}=$\frac{8 +12 + 15}{40}$=$\frac{35}{40}\frac{35}{40}$is not in the lowest term. Divide both numerator and denominator by common multiple 5$\frac{35}{40}$=$\frac{7}{8}\$