In honor of Pi Day, I baked something circular. Here is a “formula” for Black and Blue Tea Cakes, and when we’re done we’ll calculate Pi!
Preheat the oven to 350 degrees F. Lightly oil four 2 cup Pyrex glass bowls.
Mix together 1 cup unbleached wheat flour, 1 cup whole wheat flour, 3 teaspoons baking powder, 1/2 teaspoon allspice, 1/2 cup sugar, 1/4 cup sweet ground chocolate and cocoa, and 1/2 cup finely chopped almonds.
Add 2 slightly beaten eggs, 1/2 teaspoon vanilla, 3/4 cup milk, 1/4 cup vegetable oil, 1 grated fresh pear, and 1 cup blueberries. Stir together only until flour is moistened.
Pour into bowls and bake for 35-45 minutes, until a knife inserted in the center comes out clean. Cool and enjoy with a nice cup of tea or the beverage of your choice!
Now for the math:
Pi is the ratio of the circumference of any circle to its diameter. So by measuring the circumference and diameter of a circle, and dividing the circumference by the diameter, we should get close to the constant Pi, depending on how carefully we measure.
Here are my measurements:
mixing bowl circumference: 93.5 cm, diameter: 30 cm, Pi (93.5 divided by 30): 3.12
tea cake circumference: 31 cm, diameter: 9.5 cm, Pi: 3.26
measuring cup circumference: 23.5 cm, diameter: 7.5 cm, Pi: 3.13
As you can see, I came pretty close to the actual value of Pi with the measuring cup. Pi rounded to two decimal places is 3.14.
Here is a link to help you celebrate this mathematical day.