Why is the area of a circle proportional to the square of its radius? And why is that ratio the same as the ratio of the circumference to the diameter?

Learn how to calculate the areas of rectangle, triangle, and circle in Excel for a single cell or range of cells usin this formula.

One of the oldest calculus problems, finding the area of a circle, can be visualized using a pizza. By dividing it up into ever smaller slices and laying them out next to one another, eventually ...