Viết số thích hợp vào chỗ chấm:
Giải thích
\[\frac{4}{9}\,\, = \,\,\frac{{4\,\, \times \,\,6}}{{9\,\, \times \,\,6}}\,\, = \,\,\frac{{24}}{{54}}\] | \(\frac{{63}}{{135}}\,\, = \,\,\frac{{63\,\,:\,\,9}}{{135\,\,:\,\,9}}\,\, = \,\,\frac{7}{{15}}\) |
\(\frac{8}{7}\,\, = \,\,\frac{{8\,\, \times \,\,\,10}}{{7\,\, \times \,\,\,10}}\,\, = \,\,\frac{{80}}{{70}}\) | \(\frac{{55}}{{77}}\,\, = \,\,\frac{{55\,\,:\,\,\,11}}{{77\,\,:\,\,\,11}}\,\, = \,\,\frac{5}{7}\) |