3/12 or 1/4 is left of the bread
2*4
-----= 8/12 - i did this for a common denominator
3*4
8 1 9
--- + --- = --- i did this to find the total eaten
12 12 12
12 9 3 1
--- _ --- = --- or simplified as ----
12 12 12 4
the total amount of bread left is 3/12 or 1/4 (simplified)