# What is the pattern that should appear in the box?

there. I came across a puzzle from a workbook for primary school students who wish to sit in exams for enrolling to selective high schools in Sydney, which asks what is the pattern that should appear in the square box, as is shown in the following picture.

I have no idea of what rules are behind the changes of those patterns. Thanks a lot for your help!

I think the answer should be

Image number 3

Reasoning

In the top row, all the angles formed by the the intersection of lines in the
- first image are $$45^o$$ and $$90^o$$
- second image are $$60^o$$ and $$120^o$$
- third image are $$90^o$$, exclusively.

In the second row, all the angles formed by the the intersection of lines in the
- first image are $$45^o$$ and $$90^o$$
- second image are $$60^o$$ and $$120^o$$

So, the third image in the second row should be one which just has angles of $$90^o$$ and only image 3 satisfies this property.

I would not expect the logic to be more difficult than this given it is aimed at primary school students.

• Thank you, hexomino. I think your explanation is fairly plausible, considering more complicated logics for primary school students may not quite fit in the context. However, for the moment I'd like to welcome some other ideas to join in, too. Thanks again for your participation. Oct 3, 2019 at 12:19