1. 14-13,2 : (3 11/21 - 2 4/15) ,5 + 3 2/3) : (- 2 11/12)

▪1. 14-13,2 : (3 11/21 - 2 4/15) = 14 - 13,2 : (3 55/105 - 2 28/105) = 14 - 13,2 : 1 27/105 = 14 - 13,2 : 1 9/35 = 14 - 132/10 : 44/35 = 14 - 66/5 × 35/44 = 14 - 6 × 7/4 = 14 - 21/2 = 14 - 10 1/2 = 4 - 1/2 = 3 целых 1/2 = 3,5;

▪2. (-2,5 + 3 2/3) : (- 2 11/12) = (-2 1/2 + 3 2/3) : (- 2 11/12) = (-2 3/6 + 3 4/6) : (- 35/12) = 1 1/6 ÷ (-35/12) = 7/6 × (-12/35) = -2/5 = -0,4