If there are 2800 calories in every cheesecake, and each slice of cheesecake contains 350 calories, then the cheesecake has 2800/350=<<2800/350=8>>8 slices.
If Kiley ate 25% of the cheesecake, then she ate 8*0.25=<<8*0.25=2>>2 slices of cake.
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