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In page Cut (cards):

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It can be demonstrated that multiple top-to-bottom (non-Scarne's) cuts are equivalent to some single cut. In fact, knowing the size of the deck and the size of the cuts, the formula for the composite single cut is given as the sum of the sizes of the cuts modulo the size of the deck. For example, in a 10 card deck, if a 7 card cut and a 4 card cut are made, that is, 7 cards are moved from the top of the deck to the bottom and then the resulting top 4 cards are also moved to the bottom, then those two consecutive cuts are equivalent to a cut the size of (7 + 4 = 11 (mod 10)) = 1. The deck will be in the order (2,3,...,10,1).