Question

directions: write the following numbers in scie correct number of significant figures.

1. 0.0000004
2. 500,000
3. 3.870

Explanation:

1) For 0.0000004

Step1: Identify significant digits

The non - zero digit here is 4. To write it in scientific notation (which shows the number of significant figures clearly), we move the decimal point 7 places to the right.
The number in scientific notation is $4\times10^{-7}$. The number of significant figures is 1.

Step1: Analyze significant figures

If we consider the trailing zeros as not significant (when there is no decimal point to indicate otherwise), the significant digit is 5. In scientific notation, it can be written as $5\times10^{5}$ (1 significant figure). If the trailing zeros were significant (for example, if it was written as 500000.), but in the given form, the most probable is 1 significant figure.

Step1: Identify significant digits

All the digits 3, 8, 7, and 0 (the trailing zero after the decimal is significant) are significant. To show the number of significant figures, we can write it as $3.870$ (4 significant figures) or in scientific notation as $3.870\times 10^{0}$.

Answer:

$4\times10^{-7}$ (1 significant figure)

2) For 500,000