3 5/8 - 4/5 + 2 1/2 =

29/8 - 4/5 + 5/2
29/8 - (8/10+ 25/10)
29/8 - (33/10)
= 290/80 - 264/80
= 26/80
bisa di kecil kan dgn masing" dibagi 2
= 13/40

3 5/8 - 4/5 + 2 1/2 
29/8 - 4/5 + 5/2
145/40 - 32/40 + 100/40
213/40
5 13/40