Решите пожалуйста!!!
А) 1/2 + 3/8 = (4*1+3)/8 = 7/8 б) 5/12 - 1/30 = (5*5 - 1*2)/60 = (25-2)/60 = 23/60 в) 19/30 - 0,3 + 9/20 = 19/30 - 3/10 + 9/20 = (19*2 - 3*6 + 9*3)/60 = (38-18+27)/60 = 47/60