Still think you're lazy?
The average moderately active individual is estimated to take 7500 steps/ day. If he lives upto the age of 80, he would have taken 216,262,500 steps. According to Arizona State University, the average stride of a man is 2.5 feet or 30 inches. Doing the math, he would have walked a total distance of 110,000 miles or 5 times of the earth's circumference at the equator.
Fascinating, isn't it? These kind of problems that help us estimate large un-intuitive figures are known as Fermi Problems. The estimation technique is named after Enrico Fermi, an Italian physicist and the creator of the world's first nuclear reactor, the Chicago Pile-1, who was known for making very accurate estimates with little to no actual figures.
His skills with estimation was so sharp, that he was able to estimate the strength of an atomic bomb at Trinity test, simply by dropping pieces of paper and noting, how far they dropped.
Enrico Fermi, the man behind the famous fermi question
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These problems systemically reduce the error margin give staggeringly accurate results and are way more efficient than simply guessing values with little to no mathematical basis. One of the most interesting applications of this estimation technique is known as the "Fermi Problem" which contradicts the lack of evidence and high probability estimates of aliens visiting our home planet. It argues that the probability of no other intelligent life among billions of other galaxies is very low and hence they must exist. At the same time, there's no proof the above claim, unlike most of his estimates which was verified with actual results