## Elementary Algebra

$= \frac{187}{60}$
1) Turn all of the mixed numbers into fractions. 2) Find a common denominator between the first two fractions 3) Find a common denominator between the two fractions in Step #5 $= 3(\frac{2}{5}) - 4(\frac{5}{6}) + 6(\frac{7}{8})$ $= (\frac{6}{5}) - (\frac{20}{6}) + (\frac{42}{8})$ $= (\frac{6(6)}{30}) - (\frac{20(5)}{30}) + (\frac{42}{8})$ $= (\frac{36}{30}) - (\frac{100}{30}) + (\frac{42}{8})$ $= -\frac{64}{30}+ \frac{42}{8}$ $= -\frac{32}{15} + \frac{42}{8}$ $= -\frac{32(8)}{15(8)} + \frac{42(15)}{8(15)}$ $= -\frac{256}{120} + \frac{630}{120}$ $= \frac{374}{120}$ $= \frac{187}{60}$