4 Выполните умножение и деление дробей: а) 1/9 ⋅ 5/6; б) 4/15 ∶ 8/9; в) 2 1/6 ⋅ 1 5/13; г) 4 2/3 ∶ 2 6/11

а) 1/9 * 5/6 = (1*5) / (9*6) = 5/54

б) 4/15 : 8/9 = 4/15 * 9/8 = (4*9) / (15*8) = (4*3*3) / (3*5*4*2) = 3/ (5*2) = 3/10

в) 2 1/6 * 1 5/13 = 13/6 * 18/13 = (13*18) / (6*13) = 18/6 = 3

г) 4 2/3 : 2 6/11 = 14/3 : 28/11 = 14/3 * 11/28 = (14*11) / (3*28) = (14*11) / (3*14*2) = 11 / (3*2) = 11/6 = 1 5/6

Ответ: а) 5/54; б) 3/10; в) 3; г) 1 5/6