Номер 451 под цифрой 4!!!пж,даю 15 баллов!
(7 - 1 5/9 : 7/24) : 20/27 = 2 1/4 1) 1 5/9 : 7/24 = 14/9 : 7/24 = (14 * 24)/9 * 7) = 48/9 = 16/3 = 5 1/3 2) 7 - 5 1/3 = 1 2/3 3) 1 2/3 : 20/27 = 5/3 : 20/27 = (5 * 27) / (3 * 20) = 9/4 = 2 1/4