Đáp án:
e. \(\dfrac{{ - 63}}{{16}}\)
Giải thích các bước giải:
\(\begin{array}{l}
a.A = 7 - \dfrac{3}{4} + \dfrac{1}{3} - 6 - \dfrac{5}{4} + \dfrac{4}{3} - 5 + \dfrac{7}{4} - \dfrac{5}{3}\\
= \left( {7 - 6 - 5} \right) + \left( { - \dfrac{3}{4} - \dfrac{5}{4} + \dfrac{7}{4}} \right) + \left( {\dfrac{1}{3} + \dfrac{4}{3} - \dfrac{5}{3}} \right)\\
= - 4 - \dfrac{1}{4} + 0\\
= - \dfrac{{17}}{4}\\
b.B = \dfrac{1}{3}\left( { - \dfrac{4}{5} - \dfrac{6}{5}} \right)\\
= \dfrac{1}{3}.\left( { - 2} \right)\\
= - \dfrac{2}{3}\\
c.C = \dfrac{1}{{13}}\left( {\dfrac{3}{7}.\dfrac{9}{2} - \dfrac{1}{{14}}} \right)\\
= \dfrac{1}{{13}}.\left( {\dfrac{{27}}{{14}} - \dfrac{1}{{14}}} \right)\\
= \dfrac{1}{{13}}.\dfrac{{13}}{7}\\
= \dfrac{1}{7}\\
d.D = \left( { - \dfrac{3}{4} + \dfrac{2}{5}} \right).\dfrac{7}{3} + \left( {\dfrac{3}{5} - \dfrac{1}{4}} \right).\dfrac{7}{3}\\
= \dfrac{7}{3}\left( { - \dfrac{3}{4} + \dfrac{2}{5} + \dfrac{3}{5} - \dfrac{1}{4}} \right)\\
= \dfrac{7}{3}.0 = 0\\
e.E = \dfrac{7}{8}:\left( {\dfrac{2}{9} - \dfrac{1}{{18}} + \dfrac{1}{{36}} - \dfrac{5}{{12}}} \right)\\
= \dfrac{7}{8}:\left( { - \dfrac{2}{9}} \right)\\
= \dfrac{{ - 63}}{{16}}
\end{array}\)
