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Face up cards in 42 card deck = N Face up cards in 10 card deck = 10-N Face up cards in 10 card deck after flip = 10 - (10-N) = N N == N, so they are equal
by gfunk911 16y ago
Face up cards in 42 card deck = N
Face up cards in 10 card deck = 10-N
Face up cards in 10 card deck after flip = 10 - (10-N) = N
N == N, so they are equal