Cократи дроби,затем их к общему знаменателю. 4/8 и 1/4 3/7 и 2/42 20/45 и 14/35 2/10 и 1/15 20/25 и 1/3 70/100 и 25/175 7/16 и 3/6 5/8 и 18/27 75/90 и 15/60

4/8 = 1/2 и 1/4  ⇒  2/4 и 1/4,

3/7 и 2/42 = 1/21  ⇒  9/21 и 1/21,

20/45 = 4/9 и 14/35 = 2/5  ⇒  20/45 и 18/45,

2/10 = 1/5  и 1/15  ⇒  3/15 и 1/15,

20/25 = 4/5 и 1/3  ⇒  12/15 т 5/15,

70/100 = 7/10 и 25/175 = 1/7  ⇒  49/70 и 10/70,

7/16 и 3/6 = 1/2  ⇒  7/16 и 8/16,

5/8 и 18/27 = 2/3  ⇒  15/24 и 16/24,

75/90 = 5/6 и 15/60 = 1/4  ⇒  10/12 и 3/12