a) $\frac{-5}{3}$ + $\frac{1}{2}$ : $\frac{3}{4}$
= $\frac{-5}{3}$ + $\frac{2}{3}$
= -1
b) $\frac{-3}{7}$ - $\frac{4}{9}$ +$\frac{10}{7}$
= ($\frac{-3}{7}$ - $\frac{10}{7}$ ) + $\frac{4}{9}$
= $\frac{-13}{7}$ + $\frac{4}{9}$
= $\frac{-117}{28}$
c) $\frac{-7}{15}$ + $\frac{4}{15}$ - $\frac{1}{3}$
= $\frac{-7}{15}$ + $\frac{4}{15}$ - $\frac{5}{15}$
= $\frac{-8}{15}$
d) ($\frac{9}{10}$ - $\frac{4}{5}$ ) : $\frac{2}{5}$ + 1
= ($\frac{9}{10}$ - $\frac{8}{10}$) . $\frac{5}{2}$ + 1
= $\frac{1}{10}$ . $\frac{5}{2}$ +1
= $\frac{1}{4}$ + 1
= $\frac{5}{4}$
Câu 2:
a) 2x + $\frac{1}{4}$ = $\frac{3}{2}$
2x = $\frac{3}{2}$ - $\frac{1}{4}$
2x = $\frac{6}{4}$ - $\frac{1}{4}$
2x = $\frac{5}{4}$
x = $\frac{5}{4}$ : 2
x = $\frac{5}{4}$ . $\frac{1}{2}$
x = $\frac{5}{8}$
b) x + $\frac{1}{7}$ = $\frac{1}{2}$
x = $\frac{1}{2}$ - $\frac{1}{7}$
x = $\frac{7}{14}$ - $\frac{2}{14}$
x = $\frac{5}{14}$
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