During breakfast, Blanch has 15 - 4 = <<15-4=11>>11 slices left.
At lunch, she still has 11 - 2 = <<11-2=9>>9 slices left.
After the snack, there are still 9 - 2 = <<9-2=7>>7 slices left.
Finally after dinner, Blanch has 7 - 5 = <<7-5=2>>2 slices left.
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