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 ...

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 ...

The number represented by pi (π) is used in calculations whenever something round (or nearly so) is involved, such as for circles, spheres, cylinders, cones and ellipses. Its value is necessary to ...

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 ...

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, ...