10 5/18-5 8/27= 2) 25 7/32-21 1/24

10 5 /18 - 5 8/27 =5+(5/18-8/27)=5+(15/54 - 16/54)=5  -1/54= 4  53/54--------------------------------------------------------25 7/32 - 21 1/24 = 4+(7/32-1/24) = 4 + (21/96-4/96) = 4  17/96