When is zero considered significant

If a zero is found between significant digits, it is significant. Zeros can be used as (insignificant) place holders to the left of significant digits if the number is a decimal. For example, a mass of 42 g has two significant digits. Expressed in kilograms, the mass of 0.042kg should still have two significant digits.

The trailing zero to the right in the decimal place and the zero present between the non zero digit are significant.

Explanation:

The rules which describes about the significant digits are discussed below as:

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