A strawberry pie was cut into 12 slices. Mark ate 1/4 the pie. How many slices of pie did Mark eat?

If Mark ate 1/4 of the pie, that means he ate a quarter of it. We need to find a quarter of 12 slices. We can do this by dividing 12 by 4: 12/4=3. So, he ate three slices, because three is a quarter of 12.

Answer: 3 slices