## anonymous 5 years ago math help: how much gold edging is needed to do a plate with a diameter of 30cm

You need the circumference of the plate. That's given by $C=\pi d$where d is the diameter. In your case,$C=\pi \times 30cm \approx 94.248 cm$...this assumes the question is meant to be pretty basic and not take into consideration the fact that this circumference is technically infinitesimally thin...