CHICAGO (CBS) — Today’s a day when math-lovers and dessert-lovers can agree. It’s “Pi Day,” and several area bakeries and restaurants are celebrating with sales on pies.

As WBBM Newsradio’s Bernie Tafoya reports, “Pi Day” celebrates the mathematical ratio of the circumference of a circle to its diameter: an irrational number, a fraction that goes on forever, starting with the digits 3.14.

The Illinois Science Council decided to have a little fun with the day, connecting pi with the pie we like to eat.

LISTEN: WBBM Newsradio’s Bernie Tafoya reports

Monica Metzler said deals have been set up at a number of bakeries and restaruants all day. Generally, slices of pie sold for $3.14.

“Science and technology and math really does enrich all our lives; and it is fun, and it’s fun to learn, and it’s fun to think about things like this for a while,” she said.

Mariah Daley, who manages the First Slice Pie Café in Andersonville, said “definitely our Michigan sour cherry is always really popular. Our French silk and our chocolate cream are also both pretty popular pies.”

If you’d like a list of places to get pie prices on “Pi Day,” click here.

In the meantime, pi keeps on going. Most recently, it was calculated out to 2.1 trillion decimal places.