Web Puzzles

The Rector's four boys have done their best to make the dog situation at the rectory confusing. Each of the four, their names Alec, Bob, Charlie, and David, owns two dogs, and each has named his dogs after two of his brothers. Each boy has, in consequence, two doggy namesakes.

Of the eight dogs, three are cocker spaniels, three are terriers, and two are dachshunds. None of the four boys owns two dogs of the same breed. No two dogs of the same breed have the same name. Neither of Alec's dogs is named David and neither of Charlie's dogs is named Alec. No cocker spaniel is named Alec, and no terrier is named David. Bob does not own a terrier.

What are the names of the dachshunds, and who are their owners?

Solution

"And what about these two posters?"

"Those are the posters that will be hung on the south side of Red Square: as you can see they represent comrades Lenin and Marx."

"I can see that by myself. What I meant was the other two posters over there, the one with the Red Star and the one with the Hammer and Sickle."

The four posters were lined up and showed, from left to right, Lenin, Marx, the Red Star, and the Hammer And Sickle.

"Oh, they are nothing but the back of the other two. I wanted you to also see the back-faces of the posters, as these back-faces will be invisible from the inside of the Square."


"Hmmm... so enlighten me, which is the front of the poster representing the Hammer And Sickle?"
Nikita Proskoijev grinned, "I would like to test your deduction capabilities, dear comrade; a capability, I might add, which some people have had the guts to doubt. I say that all posters representing Lenin show the Hammer And Sickle on their opposite face. How would you verify this statement, in such a way that leaves no shadow of a doubt?"

"Do you mean, dear tovarisc, that I should turn these gigantic posters around to see which comrade matches the Star and which the Hammer And Sickle?"

"I have said what I have said, dear Ivanovic; it is up to you to decide what is the minimum number of posters to turn around to verify whether my statement was true or false."

Ivanovic felt very cold, as if he was in Siberia. What is the minimum number of posters, out of the four displayed, that he has to turn around to verify the statement of that cunning snake?

Solution