After losing 4.17, it came down to 100.08, so the opening price was:
100.08 + 4.17 = 104.25
To find percentage decline, we find the ratio of the "change" (which is 4.17) divided by the opening (original) price, which is 104.25. Then we multiply that fraction by 100 to get our percentage decline.
You are building your kids a small desk, where the width is 1/3 of its length. The length of the desk is 6 feet. What is it’s width? What is the area of the desk?