a) 4 1/2 : 6 + 3 2/3 = 9/2 * 1/6 + 3 2/3 = 9/12 + 3 2/3 = 9/12 + 11/3 = 9/12 + 44/12 = 53/12 = 4 5/12
b) (5 1/3 - 2 2/5) : 2 = (16/3 - 12/5) : 2 = (80/15 - 60/15) : 2 = 20/15 : 2 = 10/15 = 2/3
c) (5 1/2 - 3 1/4)^2 : 7 = (5 2/4 - 3 1/4)^2 : 7 = (2 1/4)^2 : 7 = 9/4 * 9/4 : 7 = 81/16 : 7 = 81/16 * 1/7 = 81/112
