College Mathematics Lecture Notes, Section 1.3

Thus, the best way to state your measurement is as 6.1 cm ( 0.05 cm. That way, people know exactly how precise your measurement is, and they know not to expect more precision (like 6.139 cm), and that a number of 6 cm is neglecting the full precision of the measurement. Note: 6.1 cm ( 0.05 cm … ................
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