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"#.