There's four houses next to each other, somewhere in suburb Netopia.

Johnny lives in number 3.

The red house is in between the white and yellow houses.

Mickey does not live at the end.

House number 9 is not blue and doesn’t belong to Nick.

Eric’s neighbor has an unusual pet.

Mickey lives in the yellow house with his pet giraffe.

Nick and Johnny are not neighbors.

At what number does the gorilla live?

The gorilla lives at:

Number 7

To solve this puzzle:

We have to make several assumptions that are not explicitly stated within the clues. First of all, from the information that two of the house numbers are 3 and 9, we have to assume that all of the house numbers are consecutive odd numbers. Therefore, we assume that the four houses are numbered 3, 5, 7, and 9, in that order. Second, because the only animals mentioned at all in the puzzle are a giraffe and a gorilla, we have to assume that these are the only two exotic animals living in any of these homes.

With the above assumptions:

Mickey does not live at the end, so we know he must live in either 5 or 7. His house is yellow. We also know that the red house is between the white and yellow, so we know that both the yellow and red houses are in the middle -- not on the ends. The end houses are therefore white and blue. 9 is not blue, so house 3 must be blue. Johnny lives there. House 9, then, must be white. As the red house is between the white and yellow, we know that 5 is yellow and 7 is red. Mickey lives in 5 with his giraffe. #9 is not Nick's house, so Nick must live in 7, and Eric lives in 9. Eric's neighbor has an unusual pet. That can not be the giraffe in 5, so it must be the gorilla in 7.

Image:

     3          5        7         9
blue     yellow     red     white
Johnny    Mickey    Nick     Eric
giraffe   gorilla

• Yes. In the United States, house numbers are USUALLY even on one side, odd on the other. So yes, the assumption you made is absolutely correct. You did a great job in explaining your answer, by the way. Thanks for 'playing'. Commented Apr 12, 2020 at 2:59
• Another assumption you made is that there's a blue house. Commented Apr 12, 2020 at 23:14
• @msh210 - Yes, but that's less of a leap than the other assumptions, as it is not so uncommon in these types of puzzles to indicate that an item is involved in the puzzle by saying something is NOT it. For example, "Mr. Smith is not Larry" usually implies that one of the other people in the puzzle IS Larry. Commented Apr 13, 2020 at 1:34

Unless this is a trick question where the answer is something like: a zoo.... The house number should be 7 - given that a gorilla is considered to be an unusual pet.

• On this site, you are expected to explain your reasoning, and also to spoilerize your answer. Commented Apr 12, 2020 at 2:54
• Isn't a giraffe also considered an unusual pet? Commented Apr 12, 2020 at 3:17
• @Randal'Thor , yes sir, but in your grid you will see that certain facts definitely define ( is that even proper grammar, lol ) and rule out one animal versus the other. I know you ( by your posts ) and I am sure you already got the Gorilla's address. I've see you contribute to much harder puzzles of mine. Thanks for all your edits and help to my puzzles, by the way. Commented Apr 12, 2020 at 18:07
• @JohnS. Yeah, of course the puzzle can be solved logically. My comment was just challenging this specific posted answer which deduces "gorilla" just from "unusual pet". And no worries, you make fun logic puzzles :-) With cool images, btw - are you making all the graphics yourself? Commented Apr 12, 2020 at 18:27
• @Randal'Thor, thanks for your comment. And yes, I dig through the company asset folders for something fun, or use our Dreamtime account. I'm definitely no pro in Photoshop but even simple graphics seem to help grab the kids/students attention. We use your site to prepare ex-offenders recently released for their GED. Most of my puzzles are simple logic grid based or algebra related. This new approach appears to be working, although it's getting more and more challenging to come up with new ideas lately. Any suggestions? Commented Apr 12, 2020 at 20:16