Gymnasium for Brain

Remember "Sky is the limit for those who try "

Paint the Window

My room has a square window that measures 4 feet by 4 feet. I want to paint only half the area of the window.  Bali did a wonderful job for me. Even after painting I found that the clear part of the window still remained a square and measured 4 feet from the top to bottom and 4 feet from side to side.

How is this possible?

 

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