[header] How to measure a roll of carpet [title] Measure and record the diameter of the entire roll of carpet in inches. [title] Measure and record the diameter of the hole in the center of the carpet roll in inches. [title] Measure and record the thickness of the carpet in inches. 
[title] Find the area of the entire roll of carpet. [step] Separately, find the area of the hole in the center of the roll.