Stuff:
4/8 or 1/2 of pie is left.
Mr. Vargas eats 1/4 of the whole pie.
8 slices * 1/4 = 8/4 = 2 slices.
Out of the 4 slices remaining, Mr. Vargas ate 2 slices.
That left 2 slices from the original 8 slices.
2/8 = 1/4
Answer: 1/4 of the pie remained.