Đáp án:
Giải thích các bước giải:
d. -1,4.$\frac{15}{49}$ - (80% + $\frac{2}{3}$) : 2$\frac{1}{5}$
= $\frac{-7}{5}$. $\frac{15}{49}$ - ($\frac{4}{5}$ + $\frac{2}{3}$) : $\frac{11}{5}$
= $\frac{-1}{1}$. $\frac{3}{7}$ - ($\frac{12}{15}$ + $\frac{10}{15}$). $\frac{5}{11}$
= $\frac{-3}{7}$ - $\frac{22}{15}$. $\frac{5}{11}$
= $\frac{-3}{7}$ - $\frac{2}{3}$. $\frac{1}{1}$
= $\frac{-3}{7}$ - $\frac{2}{3}$
= $\frac{-9}{21}$ - $\frac{14}{21}$
= $\frac{5}{21}$
b. $\frac{-3}{4}$ : x = $\frac{1}{2}$
x = $\frac{-3}{4}$ : $\frac{1}{2}$
x = $\frac{-3}{4}$.2
x = $\frac{-3}{2}$.1
x = $\frac{-3}{2}$