The thing about this joke is that the accountant is (kinda) right. Suppose they pass one field with about 1000 sheep and lots and lots of fields with ~5 sheep. Someone who thinks "about 1000" + 5 = "about 1000" is going to get a very wrong answer, and someone who thinks "about 1000" + 5 = "about 1005" is going to do much better.
This is also why, when combining floating-point values of different widths, it is better to say single + double -> double than single + double -> single, and why the concept of "significant figures" as commonly taught in schools is dangerous.
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The thing about this joke is that the accountant is (kinda) right. Suppose they pass one field with about 1000 sheep and lots and lots of fields with ~5 sheep. Someone who thinks "about 1000" + 5 = "about 1000" is going to get a very wrong answer, and someone who thinks "about 1000" + 5 = "about 1005" is going to do much better.
This is also why, when combining floating-point values of different widths, it is better to say single + double -> double than single + double -> single, and why the concept of "significant figures" as commonly taught in schools is dangerous.