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# bonanova

Member Since --
Offline Last Active Today, 05:19 PM

### Mafia

Today, 06:38 AM

Several of us logic-puzzle types got our feet wet playing Asylum Mafia last month.

There's a new Justice League UNLEASHED 2 Sign-ups [Mafia] game that has four openings.

I'd encourage some more of us to cross over to this genre of puzzle.

It's different, you get to lie, cheat, pretend, lynch and kill.

Add your name to the roster here.

### 8x8 KenKen challenge

29 August 2014 - 05:23 PM

KenKen is like sudoku. The numbers 1 - n fill the columns and rows of an n x n grid.

Numbers are further constrained, to obey certain mathematical operations.

Two numbers inside a box marked 3- would have to differ by 3. e.g., 5 and 8 in some order.

Three numbers in a box marked 15x would have a product of 15. 1, 3 and 5 in some order.

Here is an 8x8 KenKen puzzle where the boxes are just marked with a number, like 3 or 15.

The mathematical operation is not specified. You have to figure that out as part of the puzzle.

One hint is that a boxes that contains more than 2 numbers must be either add or multiply.

Boxes that are marked 1 must be subtract: the other operators would require identical numbers or zero.

Each box should be solved as completely as possible before solving rows or columns.

A box with 1 number contains the marked number.

A box with 2 numbers marked 15 could be either 3x5 or 7+8. Nothing else.

A box with 2 numbers marked 12 could be 2x6, 3x4, 4+8 or 5+7. Only the number 1 would be excluded.

A box with 3 numbers marked 12 permits all eight numbers.

And so forth.

This KenKen puzzle is one that I have not been able to solve.

A gold star to anyone who solves it.

Good luck

### More coin tosses

29 August 2014 - 02:43 AM

You toss a fair coin repeatedly, hoping to see an odd number of T sandwiched between two H.

e.g. H T T H H T T T T H T H ... ( 12 tosses. )

On average, how many tosses does this take?

### Prisoners sorting cards - this puzzle is not for the faint of heart

13 August 2014 - 06:31 PM

The warden is at it again. The entire prison population will be set free if the inmates can achieve a simple result. They must stack three cards, an Ace, King and Queen, on a table, in that order, with the Ace on top.

Alone and in a closed room, the warden begins the process by placing the three cards face up on a desk in some or all of three bins, appropriately marked Left, Middle, and Right. If they all occupy a single bin, only the top card is visible. If they occupy only two of the bins, then only two cards are visible, and it is impossible to tell which of the two visible cards conceals the third. Of course if they are all in separate bins, all three are visible. How the cards are initially laid out is totally up to the warden, but for the purposes of this puzzle we may assume the placement is random.

At 8:00am on the fateful day, a prisoner chosen at random enters the room and moves one of the visible cards from its bin to a different (possibly empty) bin. That is, from the top of one stack to the top of another (possibly empty) stack. The prisoner then leaves the room and is led back to his cell. He does not communicate in any way with the other inmates. Then at 9:00am, and at one-hour intervals thereafter, a second, third, etc., randomly chosen prisoner enters the room and again moves a single card from the top of one pile to the top of another. A prison guard inspects the cards after each move and informs the warden if at any time the three cards become stacked in a single bin in the desired order: Ace, King, Queen, with Ace on top.

The cards must be correctly stacked by the time the 5:00pm prisoner leaves the room, or before, for the prisoners to be released. They are all executed otherwise.

The prisoners are not permitted to work out a strategy beforehand. In fact, the prisoners do not know what they are expected to do until they enter the room. We could say that prisoners enter the room, read the above description of the problem, make their move, and then leave.

What are the prisoners' chances?

We can assume they are smart. Smart enough to be Brain Denizens.

### Auto mechanic

13 August 2014 - 04:22 AM

A retired gynecologist decided to become an auto mechanic.
He was a good student and passed the final exam with flying colors.
You are amazing, said the instructor, after the student had rebuilt an engine in record time.
You mean no one else was able to rebuild an engine? asked the doctor.
Of course, said the instructor, but no one else did it through the tail pipe!