Bài 1:
a, x - ($\frac{-1}{4}$) = $\frac{-5}{6}$ + $\frac{1}{8}$ = $\frac{-17}{24}$ x = $\frac{-27}{24}$ + ($\frac{-1}{4}$) = $\frac{-23}{24}$
b,
* ($\frac{5}{2}$ - $\frac{4}{3}$). $\frac{6}{7}$ + $\frac{9}{4}$
= $\frac{7}{6}$ - $\frac{6}{7}$ +$\frac{9}{4}$
= 1 + $\frac{9}{4}$
= 3,25
* $25^{10}$ . ($\frac{1}{5}$)$^{20}$ + ($\frac{-3}{4}$) $^{8}$ . ($\frac{-4}{3}$) $^{8}$ - $2011^{0}$
= $25^{10}$ . ($\frac{1}{5}$$^{2}$)$^{10}$ + ($\frac{-3}{4}$ . $\frac{-4}{3}$)$^{8}$ - 1
= $25^{10}$ . (0,04)$^{10}$ + 1 - 1
= (25 . 0,04)$^{10}$ + 1 - 1
= 1 + 1 - 1
= 1
