3.14159265358979...

It's Pi Day, March 14! Divide any circle's circumference by its diameter and you get pi, the infinite, never-repeating, irrational number that we all got acquainted with in eighth-grade geometry class. (Did you ever have a contest to see who could memorize pi to the greatest number of decimal places?)

In a happy coincidence, pi also a homophone of pie, a delicious concoction of pastry filled with anything from fruit to vegetables to eggs. Is this connection a little bit tenuous? Yes, we'll admit. But will we accept any excuse to talk shortcrust? Yes again!

Here are 3 delicious pies that toe the line of sweet and savory. We promise that the surface area of each is pi times the radius squared.

First, the sweet, starting with this tart that holds a whole lemon -- peel, pith, juice, and all:

Here's a pumpkin pie that's almost as genius as the discovery that all circles follow the same ratio of 3.14:

And in a turn for the savory, here's a pie with cheddar in its crust and brown butter in its filling:

Happy baking!