Ojas - Makes Squares from Squares

Room 17 are using Google Draw to do a mathematical investigation.

Can regular shapes combine to make other regular shapes?

Ojas has made squares from squares. His squares are special because each square is made up of 5 squares. When you add up all of the squares you get a pattern or sequence. Starting with 5 then 20, 45 and so on. 125 is the 5th block in this sequence. Can you work out what the 4th block would be? Put you answer in the comments below.