Cards Facing Up Puzzle - Solution

The Puzzle:

Cards Facing Up
A blind-folded man is handed a deck of 52 cards and told that exactly 10 of these cards are facing up.

How can he divide the cards into two piles (possibly of different sizes) with each pile having the same number of cards facing up?

Our Solution:

The blind-folded man divides the cards into two piles with 10 and 42 cards each.

He then flips all cards in the smaller pile.

Puzzle Author: Unknown

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