Answer: 4 3/8 feet
Explanation: First off, you want to do 15 1/2 - 6 3/4 which gives you 8 3/4. Next, to get your answer, you want to divide 8 3/4 by 2 since 8 3/4 is the TOTAL distance on both sides, not the distance from the wall to the picture on one side. After you divide, you will get a final answer of 4 3/8. Hope this helped!