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[Guest]

A follow-up question about the ring:

Would the area of ring formula - pi (R + r) (R - r) or FOIL method be used from remaining and original radius to find original square feet ? A statement with the formula says first add R and r, then subtract r from R, then multiply the product by pi.

Just curious - wanted to find by algebra.

[Guest]

Please reply. Thanks.

[Guest]

Please reply.