18/20 - 5/20 = 13/20
10/4 - z - 8/16 = 21/2 - z - 1/2 = 2 - z
It is 2 and 3 over 8.
18
9/10 minus 7/8 is 1/40
3/2 - 7/10 = 15/10 - 7/10 = 8/10 = 4/5
-5/10 + 8/10 = 3/10
(+8) - (-2) = +10
2/9 minus (negative 8/9) = 2/9 + 8/9 = 10/9
3/6 minus 2/8 is 1/4
It is: 2/7 minus 5/8 is = -19/56
8
4/8 - 2/8 = 2/8