Answering your hypothetical questions, every Tuesday. Prev Next Has humanity produced enough paint to cover the entire land area of the Earth? —Josh (Bolton, MA) This answer is pretty straightforward. We can look up the size of the world's paint industry, extrapolate backward to figure out the total amount of paint produced. We'd also need to make some assumptions about how we're painting the ground. Note: When we get to the Sahara desert, I recommend not using a brush. But first, let's think about different ways we might come up with a guess for what the answer will be. In this kind of thinking—often called Fermi estimation —all that matters is getting in the right ballpark; that is, the answer should have about the right number of digits. In Fermi estimation, you can round [1] Using the formula \(\text{Fermi}(x) = 10^{\text{round}(log_{10}x)}\), meaning that 3 roun...