Упражнение 1198 4) прошу помогите

4.  4 5/12 - 1 1/2 : ( 2 1/6 + 8/15) * 1 4/5 =  3  5/12 1) 2 1/6 + 8/15 = 13/6 + 8/15 = 65/30 + 16/30= 81/30 2) 1 1/2 : 81/30 = 3/2 * 30/81 = 15/27 3) 15/27 * 1 4/5 = 15/27 * 9/5 = 3/3 * 1/1 = 1 4) 4 5/12 - 1 = 53/12 - 12/12 = 41/12 = 3 5/12