Номер 431 пожалуйста решите

а) (6/12 + 3/8) * 12/19 = (12/24 + 9/24) * 12/19 = 21/24 * 12/19 = 21/38

б) 6/7 * (11/18 - 5/12) = 6/7 * (22/36 - 15/36) = 6/7 * 7/36 = 1/6

в) (3 1/14 - 2 5/7) * (7 - 6 3/5) = (3 1/14 - 2 10/14) * (7 - 6, 6) = 5/14 * 4/10 = 2/14 = 1/7

г) (3 1/12 - 2 3/4) * (1 1/6 - 5/12) = (3 1/12 - 2 9/12) * (1 2/12 - 5/12) = 4/12 * 9/12 = 3/12 = 1/4

д) (6 7/12 - 5 11/15) * (1 3/17 - 10/17) = (6 25/60 - 5 44/60) * (1 3/17 - 10/17) =   41/60 * 10/17 = 41/102

е) 2/3 * 9/16 - 5/24 * 2/5 - 1/6 = 3/8 - 1/12 - 1/6 = 9/23 - 2/24 - 4/24 = 7/24 - 4/24 = 3/24