40 Matchsticks Challenge!

The diagram below shows 40 matchsticks arranged in a square grid.

What is the fewest number of matchsticks that need to be removed so that there are no squares (of any size) remaining?


This is how it can be done! 

Eliminating Square in 40 Matchsticks Challenge!

What was the challenge?

All that we need to do is that remove these differently colored 9 matchsticks.

So we get, 

There can be other variations of this answer but we have to remove 9 matchsticks at least to make sure there is no square.