Up to the determination of significant figures.

When Are Zeros Significant?

When zeros appear in a measurement, there are two simple rules for determining the number of signifcant figures.

Rule 1: Zeros in the middle or to the right of a number are significant

Number Significant figures

402.7 four

42.700 five

42.7000 six

4 000 027 seven

Number	Significant figures
402.7	four
42.700	five
42.7000	six
4 000 027	seven

Rule 2: Zeros to the left of a number are not significant

Number Significant figures

0.42 two

0.042 two

0.0030 two

0.003 one

Number	Significant figures
0.42	two
0.042	two
0.0030	two
0.003	one

Sadly, there is still one potential problem when dealing with zeros in measurements and we cover that next. Before moving on, can you think what this problem might be?

More about zeros?

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