# Four Cards Puzzle - Solution

## The Puzzle:

A man sitting opposite you has four cards in his hand facing him: 2, 3, 4 and 5 (but not in that order).

He wants them placed in ascending order from his left to his right. To do this, he takes the leftmost card (from your perspective) and puts it last. He then takes the third card from the right (your right) and puts it in last place.

What was the previous order of the cards?

He wants them placed in ascending order from his left to his right. To do this, he takes the leftmost card (from your perspective) and puts it last. He then takes the third card from the right (your right) and puts it in last place.

What was the previous order of the cards?

## Our Solution:

4, 2, 5, 3 from his perspective.

By this reasoning:

From our perspective call them a,b,c,d

Leftmost (a) to end: b,c,d,a

Third card from right (c) to end: b,d,a,c

From his perspective they are now 2,3,4,5 so for us they are 5,4,3,2

b,d,a,c = 5,4,3,2

b=5, d=4, a=3, c=2

So original order a,b,c,d is 3,5,2,4, or

By this reasoning:

From our perspective call them a,b,c,d

Leftmost (a) to end: b,c,d,a

Third card from right (c) to end: b,d,a,c

From his perspective they are now 2,3,4,5 so for us they are 5,4,3,2

b,d,a,c = 5,4,3,2

b=5, d=4, a=3, c=2

So original order a,b,c,d is 3,5,2,4, or

**4,2,5,3**for him