I have small brain fade today and I believe it will be faster to get hint here than wondering for an hour.

I have list A of 100 elements. How can I create another list(B) basing on list A, that will have 10 elements, so that each element is mean of 10 elements from list A?

Thank you in advance.

```
e.g.

A = [10,10,10,10,10,20,20,20,20,20,30,30,30,30,30,40,40,40,40,40]
B = [15, 35]

```