10.
a) 5x3/6x3 +7/18 = 15/18 + 7/18 = 22/18 = 11/9
b) 7x4/3x4 - 1/12 = 28/12 + 1/12 = 29/12
c) 11/20 + 3x5/4x5 = 11/20 + 15/20 = 26/20 = 6/5
d)23/18 - 8/18 = 15/18 = 3/6 = 1/2
11.
a) 1/10 + 7x2/5x2 = 1/10 + 14/10 = 15/10 = 3/2
b) 3/2 + 13/2 = 16/2 = 8/1
c) 27/16 - 7/16 = 20/16 = 5/4
d) 10/24 + 5x4/6x4 = 10/24 + 20/24 = 30/24 = 5/4
12.
a) 1x3/13x3 + 1/39 = 3/39 + 1/39 = 4/39
b)1x3/13x3 - 1/39 = 3/39 - 1/39 = 2/39
c) 1x3/17x3 + 1/51 = 3/51 + 1/51 = 4/51
d) 1x3/17x3 - 1/51 3/51 - 1/51 = 2/51
e) 9/15 + 3x3/5x3 = 9/15 + 9/15 = 18/15 = 6/5
f) 9/15 - 3x3/5x3 = 9/15 - 9/15 = 0/15 = 0