Cách 1:
\(\frac{5}{12}:\frac{2}{5}+\frac{7}{12}:\frac{2}{5}-\frac{1}{3}:\frac{2}{5}\)
\(=\frac{5}{12}\times\frac{5}{2}+\frac{7}{12}\times\frac{5}{2}-\frac{1}{3}\times\frac{5}{2}\)
\(=\frac{25}{24}+\frac{35}{24}-\frac{5}{6}\)
\(=\frac{25}{24}+\frac{35}{24}-\frac{20}{24}\)
\(=\frac{5}{3}\)
Cách 2.
\(\frac{5}{12}:\frac{2}{5}+\frac{7}{12}:\frac{2}{5}-\frac{1}{3}:\frac{2}{5}\)
\(=\frac{5}{12}\times\frac{5}{2}+\frac{7}{12}\times\frac{5}{2}-\frac{1}{3}\times\frac{5}{2}\)
\(=\left(\frac{5}{12}+\frac{7}{12}-\frac{1}{3}\right)\times\frac{5}{2}\)
\(=\left(1-\frac{1}{3}\right)\times\frac{5}{2}\)
\(=\left(\frac{3}{3}-\frac{1}{3}\right)\times\frac{5}{2}\)
\(=\frac{2}{3}\times\frac{5}{2}\)
\(=\frac{5}{3}\)
Linz
