Đáp án:
\(A=\frac{{2017}}{{2018}}\)
Giải thích các bước giải:
\(\begin{array}{l}
A = \frac{{2017}}{{2018}} \times \frac{7}{8} + \frac{{2017}}{{2018}} \times \frac{3}{8} - \frac{{2017}}{{2018}} \times \frac{1}{4}\\
= \frac{{2017}}{{2018}} \times \left( {\frac{7}{8} + \frac{3}{8} - \frac{1}{4}} \right)\\
= \frac{{2017}}{{2018}} \times \left( {\frac{7}{8} + \frac{3}{8} - \frac{2}{8}} \right)\\
= \frac{{2017}}{{2018}} \times 1\\
= \frac{{2017}}{{2018}}
\end{array}\)
