Random thought as I randomly post sporadically

In the USA, yesterday was census day. Stand and be counted. I must admit, I still need to send in my census stuff. The USA Today published some interesting data on census participation. How does your state stack up? Notice that the highest participation rate is for states in the Midwest! Horray Midwesterners!!!! We are so responsible.

But, I was wondering. Where do these percentages come from? Let's review some math.

A percentage is mathematically described as the part over the whole times 100. In this specific example it is the number of people that responded divided by the total number of people in the state times 100.

But wait, the purpose of the census is to count the total number of people in the state. How can the percent be calculated if the total number of people isn't even known?

One equation with two unknowns cannot be solved.