Question

How do you write `0.00039` in scientific notation?

Answer 1

`0color(blue)(.0003)9 = 3.9 xx 10^color(blue)(-4)`

Explanation:

This is a small decimal which means that the number has been divided by 10 several times. We indicate this by using negative indices.

Scientific notation is written as a number with ONE digit before the decimal point which is then multiplied by a power of `10`

Count how many places the point moves and that is the index.

`0color(blue)(.0003)9 = 3.9 xx 10^color(blue)(-4)`

Answer 2

A = `3.9 * 10^-4`

Explanation:

How we get this answer is simple. In scientific notation, we'll normally start by moving the numbers other than zero up until there is one unit space occupied and at least one tenth.

Then, we will calculate how many decimal places there are in the original number and subtract one (since we have one unit space).

Thus, we have scientifically notated our number (`3.9 * 10^-4`)

All the best!