This is the same reason that Pythagorean's Theorem works. The area made up of the X and Y Regions (the squares of the two legs of the triangle) is equal to Region Z (the square of the hypotenuse)
The digit 7 would be ten times greater than the digit 7 in number 0.9750 in any number with 7 in the tenths place, for example 0.723 0.7669 0.775 1.7899
