The circumference of a circle = \(\pi d\) or \(2\pi r\). Look at the sector of the circle shown below. To calculate the length of the arc, we need to know what fraction of the circle is shown. To do ...

Evan O’Dorney leaps from his seat and snatches the chalk from his teacher’s hand. “I think it goes like this,” the eighth-grader exclaims. He has come up with a formula for the number of ways to ...

Circle to Search can now help students with homework, making it easy to search for instructions and answers without leaving the digital homework screen. Later this year, Circle to Search will be able ...

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 ...