Bạn tham khảo nhé.
Bài làm
a) ($\frac{-1}{4}$ + $\frac{7}{33}$ - $\frac{5}{3}$ ) - ($\frac{-5}{12}$ + $\frac{6}{11}$ - $\frac{48}{49}$)
= ($\frac{-5}{132}$ - $\frac{5}{3}$) - ($\frac{17}{132}$ - $\frac{48}{49}$)
= $\frac{-75}{44}$ - $\frac{-5503}{6468}$
= $\frac{-251}{294}$
b) $\frac{3}{2}$ + $\frac{5}{4}$ + $\frac{9}{8}$ + $\frac{17}{16}$ + $\frac{33}{32}$ + $\frac{65}{64}$ - 7
= $\frac{11}{4}$ + $\frac{9}{8}$ + $\frac{17}{16}$ + $\frac{33}{32}$ + $\frac{65}{64}$ - 7
= $\frac{31}{8}$ + $\frac{17}{16}$ + $\frac{33}{32}$ + $\frac{65}{64}$ - 7
= $\frac{79}{16}$ + $\frac{33}{32}$ + $\frac{65}{64}$ - 7
= $\frac{191}{32}$ + $\frac{65}{64}$ - 7
= $\frac{447}{64}$ - 7
= $\frac{-1}{64}$
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