A neat card trick

[geecee]

Take a standard 52-card deck of playing cards facing up and count off from whatever the first card is until you say "King" (for example, if a seven is the top card you would say 7-8-9-10-Jack-Queen-King). Take these cards and lay them face down and start over with another stack. Do this until all 52 cards are used up. If there are any left (where you could not count to King), hold these in your hand. Then pick up all but 3 stacks and add those cards to the ones that are in your hand. Now, with the three stacks face down on the table, turn over the top card on two of the stacks. Add the face value of these two cards together, remembering (J=11 Q=12 K=13). Count off this total from the cards you are holding. Then count off 10 more. Now count the cards left in your hand and turn over the top card on the third stack. What do you find?

Spoiler

The total of the cards left in your hand is the exact same as the top card on the third stack. Correct? Yes! Good No! Then you've made a mistake somewhere.

[geecee]

Take any nine cards from a standard 52-card deck and deal the nine cards into three piles of cards each. Pick up any pile and remember its bottom card. Drop this pile on top of one of the others, and these six on top of the last pile. The cards remain face down throughout. Hold the nine cards down and spell the value of the chosen card by dealing one card down to the table for each letter. So, if the card chosen is the Jack of Clubs, spell J A C K and drop the remaining cards on top. Pick up the packet and spell O F. As before, drop the rest of the cards on top. Pick up the packet and spell the suit of the card you selected: C L U B S. Drop the rest of the packet on top.
Now spell M A G I C and turn over this last card. What do you find?

Spoiler

This was the selected card. Correct? Yes! Good No! Then you've made a mistake somewhere.