Distant from front wall

Fibonacci... but your examples don't appear to be Fibonnaci numbers.

http://en.wikipedia.org/wiki/Fibonacci_number

You are right. I stand corrected. I had assumed that the odd ratio's of 1/3 and 1/5 (Fibonacci numbers) would naturally progress to 1/7 and 1/9, which they do not. The next would be 1/8, according to the link supplied. I am using the 1/5 ratio, at present, in my listening room.

Here is some info from the Cardas website that gives a formula for speaker placement.

My conditions do not permit the distance from back wall so I cannot speak to the exact outcome.

Speaker placement, simply stated

The distance from the center of the woofer face to the side walls is:

Room Width times .276 (RW x .276)

The distance from the center of the woofer face to the wall behind the speaker is:

Room Width times .447 (RW x .447)

This is all you need to know to place speakers in a symmetrical, rectangular room!

Here is a link to the page (there is more information and a calculator too) http://www.cardas.com/content.php?area=insights&content_id=26&pagestring=Room+Setup