Ah cupcakes! The greatest invention since sliced cakes.
How much is inside cupcakes? No one knows.
I used to work at a bakery. Among other items, we made big fancy cakes, and sold slices of them. They had names like Chocolate Decadence, fruit basket, and Chocolate Amazon cake, and we sold 'em for $2.95 a slice.
Today I work at Intel, I'm more likely to be eating cake than making it, and cake bakeries have been replaced by cupcake bakeries.
Considering this shift, I pondered the question; what portion of a regular cake does one cupcake represent?

It would be easy to check. All I had to do was to prepare two identical cake mixes, make one mix into a batch of cupcakes, the other into a layer cake.

Then I could use the quanity of cupcakes to slice the cake into a similar number of slices.
The result would be cake slices with the same cake quantity as a single cupcake.

For this experiment, I enlisted my kids. We bought Pillsbury brand strawberry Moist Supreme cake mixes for $1.02, and a $1.58 for "flavor it yourself" frosting base and flavor powders from Duncan Hines.
With three eggs and a bit of oil, the total per-cake price of these ingredients hovered very close to $2.95.

My kids are really very good at breaking eggs. In no time, we had the cake layers in the oven and were onto the cupcakes.