Expanding on the logic riddle:

[Toddsterpatriot]

Restating the riddle in the OP:

I have a deck of cards. Half are red, half are black. Every time I pull one out, it is magically replaced in the deck, and the deck is re-shuffled. FOUR scenarios in this riddle:

1) I pull one card, then another, laying them face down in front of you. The first card I chose is on your left.

I turn over the first card. It is red. What is the probability the other card is also red?
.........

2) I pull one card, then another, laying them face down in front of you. The first card I chose is on your left.

I turn over the second card (the one on your right). It is red. What is the probability the other card is red?

...........

3) I pull one card, then another. Before I lay the two cards down face-down in front of you, I shuffle them behind my back. I lay them face-down in front of you, and I turn over the card to your left. It is red.

What is the probability the card on the right is also red?
.................

4) I pull one card, then another. Before I lay the two cards down face-down in front of you, I shuffle them behind my back. I lay them face-down in front of you, and I turn over the card to your right. It is red.

What is the probability the card on the left is also red?

Still struggling to understand?