What is the length of the nail reported to the correct num ber of significant figures?

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1 Answer
Aug 18, 2017

The measurement should be "5.75 cm" with three significant figures.

Explanation:

When measuring, you record the units that you can definitely read, plus one estimated digit. In this case, the nail is definitely at least "5.5 cm". However, it is in between "5.5 cm" and "6.0 cm". It looks like it's in the middle between "5.5 cm" and "6.0 cm". Half of "0.5 cm" is "0.25 cm". So the measurement to the correct number of significant digits should be read as: "5.5 cm + 0.25 cm = 5.75 cm".