Найдите знаменатель дробей. 2/9+1/2 7/15+4/5 4/9+1/6 2/3-3/5 5/12-1/3 7/12-2/9

2/9 + 1/2 = 4/18 + 9/18 = 13/18

7/15 + 4/5 = 7/15 + 12/15 = 19/15 = 1 4/15

4/9 + 1/6 = 8/18 + 3/18 = 11/18

2/3 - 3/5 = 10/15 - 9/15 = 1/15

5/12 - 1/3  = 5/12 - 4/12 = 1/12

7/12 - 2/9 = 21/36 - 8/36 = 13/36