Ответ:80 + 7 = 87.30 + 40 = 70.57 − 50 = 7.63 − 3 = 60.80 − 20 = 60.40 + 8 = 48.13 − 7 + 5 = 6 + 5 = 11.8 + 8 − 1 = 16 − 1 = 15.9 − 7 + 10 = 2 + 10 = 12.