Difficulty: Tricky

There are 4 houses that stand in a row. One family lives in each house.

The O’Connells live next door to the Taos, but they don’t live next door to the Sosas.

The Prasads don’t live next door to the Sosas.

Who lives next door to the Prasads?

Scroll down or click for a hint, or the answer!


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Brainteaser hint

Try writing down the names of all 4 families and draw in the connections you know.

If there are 4 houses in a row, 2 families will be at the ends and have 1 neighbour each, and 2 families will have 2 neighbours.

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Brainteaser answer

Although the question asks us about the Prasads, the best place to start is looking at the Sosas.

The Sosas aren’t neighbours with the O’Connells, or the Prasads, so they have to be neighbours with the Taos. They must live at one end of the row.

The Taos are next in the row. Next to them live the O’Connells, in the third house. Finally, the Prasads live in the other end house.

So the Prasads live next to the O’Connells!

One response

  1. Martin Avatar

    The way I worked it out was:

    O’Connells (O) and Taos (T) live next to each other. This means we can have the following configuration:
    O T – –
    T O – –
    – O T –
    The other configurations would be mirrors of these.

    If we add Sosas into those configurations and remove any that have (O) and (S) next to each other, we get:
    O T S –
    O T – S
    T O – S
    – O T S

    Prasads (P) don’t live next to Sosas (S). Let’s remove any of the above that would place (P) and (S) next to each other.
    P O T S

    This means that (O) [or O’Connells] are the only ones who live next to Prasads (P).

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