Помогите пожалуйста решить примеры по действиям

 1. (0.02 * 0.01 - 0.01) / 0.25 - 3/8  1) 0.02 * 0.01 = 2/100 * 1/100 = 2/10000 2) 2/10000 - 0.01 = 2/10000 - 1/100 = 2/10000 - 100/10000 = -98/10000 3) -98/10000 / 0.25 = -98/10000 * 1/4 = -392/10000 4) -392/10000 - 3/8 = -392/10000 - 3750/10000 = -4142/10000 = -0.4142  2. -3/4 + 8.5 * (0.021 / 0.01 - 2.51) 1) 0.021 / 0.01 = 21/1000 / 1/100 = 2100/1000 = 2.1 2) 2.1 - 2.51 = -0.41 3) 8.5 * (-0.41) = 8 1/2 * (-41/100) = -(17/2 * 41/100) = -697/200 = -3 97/200 = -3.485 4) -3/4 - 3.485 = -0.75 - 3.485 = -4.235  3. (0.15 - 0.15 * 6.4) / (-3/8 + 0.175) 1) 0.15 * 6.4 = 0.96 2) 0.15 - 0.96 = -0.81 3) -3/8 + 0.175 = -3/8 + 175/1000 = -3/8 + 35/200 = -3/8 + 7/40 = -15/40 + 7/40 = -8/40 = -1/5 = -0.2 4) -0.81 / -0.2 = 4.05  4. (1.6 * 2.15 - 0.23) / (3.45 - 3 3/4)  1) 1.6 * 2.15 = 1 6/10 * 2 15/100 = 16/10 * 215/100 = 3440/1000 = 3.44 2) 3.44 - 0.23 = 3.21 3) 3.45 - 3 3/4 = 3.45 - 3.75 = -0.3  4) 3.21 / -0.3 = -10.7