Đáp án:
b. -1
Giải thích các bước giải:
\(\begin{array}{l}
a.\dfrac{5}{6} - \dfrac{1}{6} + \dfrac{6}{7} + \dfrac{7}{3} = \dfrac{2}{3} + \dfrac{7}{3} + \dfrac{6}{7}\\
= 3 + \dfrac{6}{7} = \dfrac{{21 + 6}}{7} = \dfrac{{27}}{7}\\
c.\dfrac{5}{{11}}.\dfrac{7}{{15}}.\left( { - \dfrac{{11}}{5}} \right).\left( { - 30} \right)\\
= \dfrac{5}{{11}}.\dfrac{7}{{15}}.\dfrac{{11}}{5}.30\\
= \dfrac{{5.7.11.3.2.5}}{{11.3.5.5}}\\
= 7.2 = 14\\
d.\dfrac{3}{{11}}\left( { - \dfrac{5}{9} - \dfrac{{13}}{{18}}} \right)\\
= \dfrac{3}{{11}}.\left( {\dfrac{{ - 10 - 13}}{{18}}} \right)\\
= \dfrac{3}{{11}}.\dfrac{{ - 23}}{{18}} = - \dfrac{{23}}{{66}}\\
e.\left( {\dfrac{{32}}{{15}}.\dfrac{9}{{17}}.\dfrac{3}{{32}}} \right).\left( { - \dfrac{{17}}{3}} \right)\\
= - \dfrac{{9.3.17}}{{15.17.3}} = - \dfrac{9}{{15}} = - \dfrac{3}{5}\\
b.\dfrac{5}{3} + \dfrac{1}{4} - \dfrac{8}{3} - \dfrac{7}{4} + \dfrac{3}{2}\\
= - 1 - \dfrac{3}{2} + \dfrac{3}{2} = - 1
\end{array}\)
