# Calculate the answer. How would you express it in scientific notation? (1,632) (4.0 xx 10^4)?

Sep 4, 2016

"1,632" × 4.0 × 10^4 = 6.5 × 10^7

#### Explanation:

Here are the three rules you need.

1. All $\textcolor{red}{\text{non-zero digits}}$ are significant.
2. $\textcolor{red}{\text{Trailing zeroes in the decimal portion}}$ of a number are significant.
3. In multiplication and division, color(red)("you round the answer to have"
$\textcolor{red}{\text{the same number of significant digits as the number with the}}$
$\textcolor{red}{\text{fewest significant figures}}$.

You used a period as a decimal separator in 4.0, so I assume you are using the comma as a thousands separator in 1,632.

$\text{1,632}$ has four significant figures.

4.0 × 10^4 has two significant figures.

The answer can have only two significant figures.

"1,632" × 4.0 × 10^4 = 6.5 × 10^7