When making a circle skirt, a piece of fabric bounded by two concentric circular lines is required. The inner circle forms the waist of the skirt and the outer hem. For a girl with a waist circumference of [[$ 60 $]] cm, we want to sew a skirt that is [[$ 60 $]] cm long. How wide must the fabric be in order to cut the circular piece needed for the skirt? Allowances and hems do not need to be considered. (Source: Finnish matriculation exam spring 1998)



Answer: The width of the fabric must be at least cm.