Lesson number one on this blog "Seeing isn't Always Believing."
Let's start by stating the not so obvious. Square A and Square B below are the exact same color. Hard to believe isn't it?
I look at this and find it hard to believe. But I used the extension in Firefox called colorzilla which provides you with an eyedropper tool. I checked both of squares and sure enough the RGB values of the grays in both square A and square B are 120-120-120.
That wasn't good enough for my 11 year old daughter she printed the picture out, cut out the squares and put them next to each other an sure enough they were the same exact shade of gray.
The squares marked A and B are the same shade of gray.