Answer & Steps:
I just left everything in fraction form unless it's equal to a whole number. Wasn't sure how you wanted it to be simplified
16)
+
=
+
= 11/12
17) 1/2 + 2/5 = 5/10 + 4/10 = 9/10
18) 3/10 + 4/5 = 3/10 + 8/10 = 11/10
19) 3/4 + 3/8 = 6/8 + 3/8 = 9/8
20) 2/7 + 1/2 = 4/14 + 7/14 = 11/14
21) 1/6 + 3/4 = 2/12 + 9/12 = 11/12
22) 10/15 + 2/5 = 10/15 + 6/15 = 16/15
23) 1/2 + 4/9 = 9/18 + 8/18 = 17/18
24) 2/3 + 3/5 = 10/15 + 9/15 = 19/15
25) 3/4 + 3/12 = 9/12 + 3/12 = 12/12 = 1
26) 5/6 + 1/18 = 15/18 + 1/18 = 16/18 = 8/9
27) 1/3 + 5/6 = 2/6 + 5/6 = 7/6
28) 3/4 + 5/6 = 9/12 + 10/12 = 19/12
29) 1/3 + 2/7 = 7/21 + 6/21 = 13/21
30) 5/12 + 3/8 = 10/24 + 9/24 = 19/24
31) 3/5 + 1/6 = 18/30 + 5/30 = 23/30