two pizzas was cut into 8 slices each. which makes a total of 16 slice.
on Friday she ate 1/4 of a pizza which is 2 slices. that leaves her with 14 slice out of 16. and on Saturday she ate 3 slices that leaves here with 11 slices out of 16. which means she remained with one whole pizza plus 3 slices from the other one.
11/16