Counting Cards
Maggie of St Anne's School sent the following partial solution, well done Maggie.
You have to arrange the cards in a certain order . For example,
the order for 1 2 3 4 5 would be 2 4 1 3 5
O...N...E
1...2...3
T...W...O
4...5...1
T...H...R...E...E
2...4...5...2...4
F...O...U...R
5...2...5...2...
F...I...V...E
5...5...5...5
So the cards would be arranged with
Ace in position 3
Two in position 1
Three in position 4
Four in position 2
Five in position 5
There were a number of other anonymous solutions and a solution from Andrei of School 205 Bucharest. Here is one method suggested by one person:
Let's say you have 10 cards - imagine 10 positions that represent the order of the cards in the pack
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
Then you can place each card in turn in each position - using up the space so:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
|
O
|
N
|
1
|
T
|
W
|
2
|
T
|
H
|
R
|
E
|
but you run out of room before you can spell out THREE so you go back to the beginning and 3 will go in position 1. The you start spelling FOUR but you have to jump over position 3 because it has a 1 in it and position 6 because it has a 2 in it, so 4 ends up in position 7:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
|
3
|
F
|
1
|
O
|
U
|
2
|
4
|
So you end up with:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
|
3
|
5
|
1
|
8
|
10
|
2
|
4
|
6
|
7
|
9
|
This method works for any number of cards and whether you use their names or their values.
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