The radius of a circle or a sphere is the distance between the center and the edge. The radius can be used to calculate a circle's diameter, area and circumference. Likewise, a sphere's volume is ...

The ability to round a number to a number of decimal places or to a number of significant figures means that answers can be written to an agreed degree of accuracy. Watch the video to learn how ...

MATHEWS, G. A Triangle that gives the Area and Circumference of any Circle, and the Diameter of a Circle equal in Area to any given Square. Nature 93, 110 (1914 ...

To calculate the sector area, first calculate what fraction of a full turn the angle is. Calculate the area of this sector which has a 60° angle to one decimal place. 60° is one sixth of a full turn ...