The circumference of a circle is the distance around the shape. 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 ...

Now for the important part. Today, as you may know, is Pi Day. Why today? Because it’s March 14—yes, 3/14—and 3.14 is the value of pi to two decimals. Of course, the actual number continues to an ...

Diameter (d) is the distance across the circle through the center. Since the diameter passes through the center and connects ...

Scientific American presents Math Dude by Quick & Dirty Tips. Scientific American and Quick & Dirty Tips are both Macmillan companies. Throughout history, circles have symbolized many things: unity, ...