Tính: 3/5 : 2/4

Lời giải

\(\frac{3}{5}:\frac{2}{4} = \frac{3}{5} \times \frac{4}{2} = \frac{{3 \times \bcancel{2} \times 2}}{{5 \times \bcancel{2}}} = \frac{6}{5}\)

\(\frac{2}{3}:\frac{1}{7} = \frac{2}{3} \times \frac{7}{1} = \frac{{2 \times 7}}{{3 \times 1}} = \frac{{14}}{3}\)

\(\frac{1}{{10}}:\frac{1}{9} = \frac{1}{{10}} \times \frac{9}{1} = \frac{{1 \times 9}}{{10 \times 1}} = \frac{9}{{10}}\)