5 4 ⋅ 3 7 {\displaystyle {\frac {5}{4}}\cdot {\frac {3}{7}}} = 5 ⋅ 3 4 ⋅ 7 = 15 28 {\displaystyle ={\frac {5\cdot 3}{4\cdot 7}}={\frac {15}{28}}}
