9. Выполните вычитание: a) -3,6-4,7 б) 6,3-(-8,1) в) 4 1/3 - 5 2/7 г) -6 5/24 - (-5 13/30)

a) -3.6 - 4.7 = -8.3 б) 6.3 - (-8.1) = 6.3 + 8.1 = 14.4 в) 4 1/3 - 5 2/7 = 13/3 - 37/7 = (13*7 - 37*3) / 21 = (91 - 111) / 21 = -20/21 г) -6 5/24 - (-5 13/30) = -6 5/24 + 5 13/30 = -6 25/120 + 5 52/120 = -1 + (52-25)/120 = -1 + 27/120 = -1 + 9/40 = -40/40 + 9/40 = -31/40