а) 5/9 и 7/18 = 10/18 и 7/18
б) 2/3 и 10/21 = 14/21 и 10/21
в) 5/7 и 3/4 = 20/28 и 21/28
г) 9/14 и 13/20 = 90/140 и 91/140
а) 5/9 и 7/18 = 10/18 и 7/18
б) 2/3 и 10/21 = 14/21 и 10/21
в) 5/7 и 3/4 = 20/28 и 21/28
г) 9/14 и 13/20 = 90/140 и 91/140