5/9 : 2/7; 7/18 : 14/27; 3/7:21; 15:2/5; 3:5; 6:12

Решите задачу:

$\frac{5}{9} : \frac{2}{7} = \frac{5*7}{9*2} = \frac{35}{18} = 1\frac{17}{18}\\\\\frac{7}{18} : \frac{14}{27} = \frac{7*27}{18*14} = \frac{1*3}{2*2} = \frac{3}{4} = 0,75\\\\\frac{3}{7} : 21 = \frac{3}{7*21} = \frac{1}{7*7} = \frac{1}{49}\\\\15 : \frac{2}{5} = \frac{15*5}{2} = \frac{75}{2} = 37\frac{1}{2} = 37,5\\\\3:5 = \frac{3}{5} = 0,6\\\\6:12 = \frac{6}{12} = \frac{1}{2} = 0,5$