2.2
Diameter is half of the radius. Times it by 2.
Divide the circumference by Pi (3.1416)
2.54cm(254mm)
If you want to convert that to meters, you can multiply by 0.9, approximately.
50 diameter to length
2.2
To convert diameter to area , you will need to divide the diameter by two so as to get the radius. The result you get, square it and them multiply it by 3.14 to find the area.
381mm (H) X 254mm (W)
Diameter is half of the radius. Times it by 2.
Ddryy
254mm is 25.4cm (divide mm by 10).
381mm (H) X 254mm (W)
25.5mm
7
2.375
2.54cm is 1 inch 254mm is 1 inch