I don’t know about that. The number of digits in some of these examples are clearly pointless if not misleading, trying to convey an unwarranted confidence in an estimate, but some other examples have a sense.

In the case of the SUV, the quoted 35.4 inches correspond to 90cm. The 7.9-inch display of an iPad mini has a 20cm diagonal. Conversely, 8.9cm should likely be understood as 3½ inches. The extra digits are simply an artifact due to how the the available information is presented. On the same line, an 8-bit converter reporting a measurements of .19140625 does not claim to have 7 significant digits, the number of significant digits is still 2.4 (i.e. 8 bits, or two hexadecimal digits), but in order to convey those 2.4 digits you might need 7 digits.

A difference between 8.95% and 9.00% in tax rates, correspond to a difference of 500$ on a yearly income of 100k: small compared to the yearly income, but not a negligible amount for some instant gratification, be it luxury shoes or a top-of-the-rank iPad.

I often wondered why our snow parking ticket was $37? How did the city come up with that number!

I don’t know about that. The number of digits in some of these examples are clearly pointless if not misleading, trying to convey an unwarranted confidence in an estimate, but some other examples have a sense.

In the case of the SUV, the quoted 35.4 inches correspond to 90cm. The 7.9-inch display of an iPad mini has a 20cm diagonal. Conversely, 8.9cm should likely be understood as 3½ inches. The extra digits are simply an artifact due to how the the available information is presented. On the same line, an 8-bit converter reporting a measurements of .19140625 does not claim to have 7 significant digits, the number of significant digits is still 2.4 (i.e. 8 bits, or two hexadecimal digits), but in order to convey those 2.4 digits you might need 7 digits.

A difference between 8.95% and 9.00% in tax rates, correspond to a difference of 500$ on a yearly income of 100k: small compared to the yearly income, but not a negligible amount for some instant gratification, be it luxury shoes or a top-of-the-rank iPad.

I always liked the news report that said that the temperature of a particular star was 10,000,000,273.16 C