1) 5\48 + 7\36
= 5/48 + 7/36
= (53)/(483) + (72)/(362)
= 15/144 + 14/144
= 29/144

2) 17\24 - (1\5 + 5\24)
= 17/24 - (1/5 + 5/24)
= 17/24 - (4/20 + 5/24)
= 17/24 - (4/20 + 5/24)
= 17/24 - (24/60 + 5/24)
= 17/24 - (24/60 + 15/60)
= 17/24 - 39/60
= 340/480 - 312/480
= 28/480
= 7/120