Đáp án:
Giải thích các bước giải:
\(\begin{array}{l}a)\,\frac{8}{5} + \frac{7}{6} + \frac{5}{9} - 2\\ = \frac{8}{5} + \frac{{21}}{{18}} + \frac{{10}}{{18}} - 2\\ = \frac{8}{5} - 2 + \frac{{31}}{{18}}\\ = \frac{{ - 2}}{5} + \frac{{31}}{{18}}\\ = \frac{{119}}{{90}}\end{array}\)
\(\begin{array}{l}b)\,3 - \frac{5}{6} - \frac{4}{9} + \frac{{32}}{{24}}\\ = 3 - \frac{5}{6} - \frac{4}{9} + \frac{4}{3}\\ = 3 - \frac{{15}}{{18}} - \frac{8}{{18}} + \frac{{24}}{{18}}\\ = 3 + \frac{{ - 15 - 8 + 24}}{{18}}\\ = 3 + \frac{1}{{18}}\\ = 3\frac{1}{{18}}\end{array}\)
