(1)..7/10 + 1/10 = 8/10 = 4/5(2)..5/9 + 4/9 = 9/9 = 1(3)..8/15 + 3/15 = 11/15(4)..9/14 + 3/14 = 12/14 = 6/7(5)..3/5 + 8/5 = 11/5 (6)..4/15 - 3/15 = 1/15(7)..7/8 - 5/8 = 2/8 = 1/4(8)..5/3 - 2/3 = 3/3 =...