Zebra Puzzle or Einstein Puzzle

This puzzle has been attributed both to Lewis Carroll and to Albert Einstein:

1. There are five houses in a row. Each of the houses is painted a different color, and their occupants come from different countries, own different pets, drink different beverages, and smoke different cigarette brands.
2. The Englishman lives in the red house.
3. The Spaniard owns the dog.
4. Coffee is drunk in the green house.
5. The Ukrainian drinks tea.
6. The green house is immediately to the right (your right) of the ivory house.
7. The Old Gold smoker owns snails.
8. Kools are smoked in the yellow house.
9. Milk is drunk in the middle house.
10. The Norwegian lives in the first house.
11. The man who smokes Chesterfields lives in the house next to the man with the fox.
12. Kools are smoked in the house next to the house where the horse is kept.
13. The Lucky Strike smoker drinks orange juice.
14. The Japanese smokes Parliaments.
15. The Norwegian lives next to the blue house.

Who drinks water? Who owns the zebra?

Well, here is effort to simplify the solution 


From Wikipedia : The puzzle is often called Einstein's Puzzle or Einstein's Riddle because it is said to have been invented by Albert Einstein as a boy; it is also sometimes attributed to Lewis Carroll. However, there is no known evidence for Einstein's or Carroll's authorship and the Life International version of the puzzle mentions brands of cigarette, such as Kools, that did not exist during Carroll's lifetime or Einstein's boyhood. 
 

Simplified Solution of Zebra Puzzle or Einstein Puzzle

What was the puzzle?

Let's recollect the given clues once again.

1. There are five houses in a row. Each of the houses is painted a different color, and their occupants come from different countries, own different pets, drink different beverages, and smoke different cigarette brands.
2. The Englishman lives in the red house.
3. The Spaniard owns the dog.
4. Coffee is drunk in the green house.
5. The Ukrainian drinks tea.
6. The green house is immediately to the right (your right) of the ivory house.
7. The Old Gold smoker owns snails.
8. Kools are smoked in the yellow house.
9. Milk is drunk in the middle house.
10. The Norwegian lives in the first house.
11. The man who smokes Chesterfields lives in the house next to the man with the fox.
12. Kools are smoked in the house next to the house where the horse is kept.
13. The Lucky Strike smoker drinks orange juice.
14. The Japanese smokes Parliaments.
15. The Norwegian lives next to the blue house.

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STEP 1 :

As per clue (1), let's create a table like below, and then fill the data one by one.

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STEP 2 :

As per clue (9),(10) and (15),

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STEP 3 :

As per (2), Englishman lives in red house, that means it can't be first house. Also, (6) points that green house is next to ivory. So, ivory-green can't be at 1-2 positions. But those can be at 3-4 with red at 5 or at 4-5 with red at 3.

In short, only color left for 1 is yellow. And as per (8), Kools are smoked in the yellow house. 

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STEP 4 :

Now as per (12), Kools are smoked in the house next to the house where the horse is kept.

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 STEP 5 :

Let's assume the red house of Englishman is at no.5 then Ivory-Green are at no.3-4.
Since as per (4), green house owner drinks coffee, and only position left for Ukrainian drinking tea pointed by (5) is house no.2.

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STEP 6 :

Now the luck strike smoker drinking orange juice pointed by (13) has only position and that is house no.5. That leaves only drink available for house 1 as water.

As per (3), Spaniard who owns dog has houses 3 and 4 available but for Old Gold smoker (pointed by (7)) also available houses are 3 and 4 again.

If Old Gold smoker occupies house 3 then Spaniard who own dog would have house 4. In that case, there will be no position would be left for Japanese smoking Parliaments (Clue no.14).

Same can be proved if Old Gold smoker occupies house no.4.

Hence, our assumption made in step 5 is wrong. So, Red house must be at 3 owned by Englishman.

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STEP 7 :

So if Englishman's red house is at no.3 then at no.4 & 5 there must be ivory and green houses where coffee is drink in green house.

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STEP 8 :

Now, for Lucky Strike smoker who drinks orange juice (clue 13) and Ukrainian who drinks tea (clue 5) only available houses are (see above table) house no.2 & 4. That is, 2 and 4 are occupied by tea & orange juice drinkers (order yet unknown). With that, we can conclude that the drink in first house is Water.

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STEP 9 : 

If we assume that Lucky Striker smoker who drinks Orange juice (clue 13) live in house no.2 then Ukrainian who drinks tea (clue 5) has to be in house no.4. With that, Japanese who smokes Parliament (clue 14) need to be in the house no.5. No house is left for Spaniard who owns the dog (clue 3) as house no.2 is already occupied by pet horse. 

That's why the Lucky Strike smoker with Orange juice as drink must be in house no.4.

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STEP 10 : 

Now, if Lucky Strike smoker (clue 13) is living in house no.4 then Ukrainian who drinks tea (clue 5) must be in house no.2. With that, Japanese who smokes Parliament (clue 15) needs to be in house no.5 and Spaniard who owns dog (clue 3) needs to be in house no.4.

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STEP 11 :

In the end, for Old Gold smoker (clue 7) only house left is house no.3. And as per clue 11,Chasterfield smoker needs to be in the house followed by fox owner. Hence, they must be in the house no.1 and 2 respectively. Finally, the only pet left for house no.5 is Zebra.

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CONCLUSION : 

The final table looks like - 

Now, finding answers of given questions is easy from the table.

Who drinks water? 
- Norwegion

Who owns the zebra?  
- Japanese