Điền dấu >, <, = thích hợp vào chỗ chấm:
a) \(\frac{{15}}{9} - \frac{1}{2}\,\,\)< \(\frac{3}{2} + \frac{2}{9}\) Giải thích: \(\frac{{15}}{9} - \frac{1}{2}\,\, = \,\,\frac{{30}}{{18}}\,\, - \,\frac{9}{{18}}\,\, = \,\,\frac{7}{6} = \frac{{21}}{{18}}\) \(\frac{3}{2} + \frac{2}{9}\) = \(\frac{{27}}{{18}} + \,\frac{4}{{18}}\,\,\)=\(\frac{{31}}{{18}}\) \(\frac{{21}}{{18}}\,\, < \,\,\frac{{31}}{{18}}\) Vậy: \(\frac{{15}}{9} - \frac{1}{2}\,\,\, < \,\,\frac{3}{2} + \frac{2}{9}\) | c) \(\frac{1}{5} \times \frac{5}{4}\,\, < \,\,\frac{1}{2}:\frac{3}{2}\) Giải thích: \(\frac{1}{5} \times \frac{5}{4}\,\,\, = \,\,\frac{1}{4}\, = \frac{3}{{12}}\) \(\frac{1}{2}:\frac{3}{2}\,\, = \,\,\frac{1}{3} = \frac{4}{{12}}\) \(\frac{4}{{12}}\,\,\, > \,\,\,\frac{3}{{12}}\) Vậy: \(\frac{1}{5} \times \frac{5}{4}\,\, < \,\,\frac{1}{2}:\frac{3}{2}\) |