This is missing some information. For instance, it does not say what 84 is. Is it the radius, the circumference? See the link below for a step by step guide to finding a diameter.
Circumference equals pi times diameter; so C = 84*pi or about 263.9.
84 degrees is.
For any circle . . .Diameter = circumference/pi .
circumference = 84*pi
84 units x 3.1416 = 264 units (approx)
the combined diameter of all the outer planets is 363,546 kilometers, or 84% the diameter of the sun.
A circumference of 263.89 cm
84/3.14 =27 So the diameter of this circle is about 27 inches
The area of a circle, in terms of pie, with a diameter of 36 is: about 324pi
Diameter = 84 in Radius = 42 in = 3.5 feet Area of circle = pi x r x r = 3.1415 x 3.5 x 3.5 =38.483 square feet
If you are saying the diameter of a cup is 8 cm and 4 mm and you want to know what that is in mm, the answer is 84.
84