Cho biểu thức

a) $A = (8 - \frac{2}{3} + \frac{1}{2}) - (5 - \frac{7}{3} - \frac{3}{2}) - (\frac{5}{3} + \frac{5}{2} + 4)$

$A = (\frac{48}{6} - \frac{4}{6} + \frac{3}{6}) - (\frac{30}{6} - \frac{14}{6} - \frac{9}{6}) - (\frac{10}{6} + \frac{15}{6} + \frac{24}{6})$

$A = \frac{47}{6} - \frac{7}{6} - \frac{49}{6} = \frac{- 3}{2}$

b) $A = (8 - \frac{2}{3} + \frac{1}{2}) - (5 - \frac{7}{3} - \frac{3}{2}) - (\frac{5}{3} + \frac{5}{2} + 4)$

$A = 8 - \frac{2}{3} + \frac{1}{2} - 5 \frac{7}{3} + \frac{3}{2} - \frac{5}{3} - \frac{5}{2} - 4$

$A = (8 - 5 - 4) + (\frac{- 2}{3} + \frac{7}{3} - \frac{5}{3}) + (\frac{1}{2} + \frac{3}{2} - \frac{5}{2})$

$A = - 1 + 0 - \frac{1}{2} = \frac{- 3}{2}$