Hi Tony,

re:
> I have noticed that the two areas of the two items do not match

Well the surface area of your cone is: 503.22 and the surface area of your flattened one is 503.35 . So they are close to matching.

What is your construction process?

If you are copying a numeric length somewhere maybe you need to temporarily increase the number of decimal places that will be shown under Options > General > "Decimal display" to improve the accuracy.

- Michael