a) Điền số thích hợp vào chỗ chấm 2/5 = 2 × 3/5 × 3 = . . . . . .
a) Điền số thích hợp vào chỗ chấm
\(\frac{2}{5} = \frac{{2 \times 3}}{{5 \times 3}} = \frac{6}{{15}}\) | \(\frac{5}{8} = \frac{{5 \times 5}}{{8 \times 5}} = \frac{{25}}{{40}}\) | \(\frac{6}{7} = \frac{{6 \times 3}}{{7 \times 3}} = \frac{{18}}{{21}}\) |
\(\frac{{18}}{{45}} = \frac{{18:9}}{{45:9}} = \frac{2}{5}\) | \(\frac{{12}}{{30}} = \frac{{12:6}}{{30:6}} = \frac{2}{5}\) | \(\frac{{20}}{{35}} = \frac{{20:5}}{{35:5}} = \frac{4}{7}\) |
\(\frac{3}{7} = \frac{{3 \times 9}}{{7 \times 9}} = \frac{{27}}{{63}}\) | \(\frac{1}{5} = \frac{{1 \times 7}}{{5 \times 7}} = \frac{7}{{35}}\) | \(\frac{2}{3} = \frac{{2 \times 5}}{{3 \times 5}} = \frac{{10}}{{15}}\) |
\(\frac{{27}}{{45}} = \frac{{27:9}}{{45:9}} = \frac{3}{5}\) | \(\frac{{18}}{{63}} = \frac{{18:9}}{{63:9}} = \frac{2}{7}\) | \(\frac{{24}}{{64}} = \frac{{24:8}}{{64:8}} = \frac{3}{8}\) |
b) Điền số thích hợp vào chỗ chấm
\(\frac{1}{7} = \frac{5}{{35}} = \frac{{10}}{{70}}\) | \(\frac{2}{9} = \frac{4}{{18}} = \frac{{20}}{{90}}\) | \(\frac{1}{8} = \frac{3}{{24}} = \frac{{12}}{{96}}\) |
\[\frac{2}{5} = \frac{6}{{15}} = \frac{{18}}{{45}}\] | \(\frac{1}{3} = \frac{3}{9} = \frac{{15}}{{45}}\) | \(\frac{3}{5} = \frac{9}{{15}} = \frac{{27}}{{45}}\) |