A. \(\frac{1}{2}=\frac{2}{4}=\frac{4}{8}=\frac{3}{6}\)
B> \(\frac{1}{4}=\frac{2}{8}=\frac{3}{12}=\frac{5}{20}\)
C. \(\frac{2}{5}=\frac{8}{20}=\frac{10}{25}\)
Câu 2.
a\(\frac{5}{7}=\frac{10}{14}=\frac{15}{21}=\frac{20}{28}=\frac{25}{35}\)b.. \(\frac{4}{9}=\frac{8}{18}=\frac{12}{27}=\frac{16}{36}=\frac{20}{45}=\frac{24}{54}\)