Сократить дроби нужным способом: 15/18; 24/30; 28/32; 21/15:75/45; 38/66; 54/90; 36/84; 49/56; 55/77; 26/65; 51/85:

Преобразовываем дробные числа до несократимых дробей:

1) 15/18 = (3 х 5) / (3 х 6) = 5/6;

2) 24/30 = (6 х 4) / (6 х 5) = 4/5;

3) 28/32 = (4 х 7) / (4 х 8) = 7/8;

4) 21/15 = (3 х 7) / (3 х 5) = 7/5;

5) 75/45 = (15 х 5) / (15 х 3) = 5/3;

6) 38/66 = (2 х 19) / (2 х 33) = 19/33;

7) 54/90 = (18 х 3) / (18 х 5) = 3/5;

8) 36/84 = (12 х 3) / (12 х 7) = 3/7;

9) 49/56 = (7 х 7) / (7 х 8) = 7/8;

10) 55/77 = (11 х 5) / (11 х 7) = 5/7;

11) 26/65 = (13 х 2) / (13 х 5) = 2/5;

12) 51/85 = (17 х 3) / (17 х 5) = 3/5.