Bỏ dấu ngoặc rồi tính.
BÀI TẬP
Bài 1. Bỏ dấu ngoặc rồi tính.
a) $(\frac{-3}{8})+(\frac{7}{9}-\frac{5}{8})$
b) $\frac{4}{9}-(\frac{3}{7}+\frac{2}{9})$
c) $[(\frac{-2}{5})+\frac{1}{3}]-(\frac{3}{5}-\frac{1}{4})$
d) $(1\frac{1}{2}-\frac{3}{4})-(0.25+\frac{1}{2})$
a) $(\frac{-3}{8})+(\frac{7}{9}-\frac{5}{8})=(\frac{-3}{8})+\frac{7}{9}-\frac{5}{8}=(\frac{-3}{8})+(\frac{-5}{8})+\frac{7}{9}=-1+\frac{7}{9}=\frac{-2}{9}$
b) $\frac{4}{9}-(\frac{3}{7}+\frac{2}{9})=\frac{4}{9}-\frac{3}{7}-\frac{2}{9}=\frac{4}{9}-\frac{2}{9}-\frac{3}{7}=\frac{2}{9}-\frac{3}{7}=\frac{-13}{63}$
c) $[(\frac{-2}{5})+\frac{1}{3}]-(\frac{3}{5}-\frac{1}{4})=(\frac{-2}{5})+\frac{1}{3}-\frac{3}{5}+\frac{1}{4}=(\frac{-2}{5})+(\frac{-3}{5})+\frac{1}{3}+\frac{1}{4}=-1+\frac{7}{12}=\frac{-5}{12}$
d) $(1\frac{1}{2}-\frac{3}{4})-(0.25+\frac{1}{2})=\frac{3}{2}-\frac{3}{4}-\frac{1}{4}-\frac{1}{2}=\frac{3}{2}-\frac{1}{2}-\frac{3}{4}-\frac{1}{4}=0$
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