Question

What is `0.0000004` in scientific notation?

Answer 1

`4 xx 10^-7`

Explanation:

You need one digit before the decimal point and then a power of 10.

The decimal is formed by dividing by 10 seven times. The index will be negative.

`4 xx 10^-7`

Probably too late for the quiz, but you can learn it now for next time . EZ

Answer 2

`0.000 000 4 = 4xx10^-7`

Explanation:

`0.000 000 4 = 4xx10^-7`

You have to move the decimal point until it is on the right side of the 4, to give `4.0` Count how many places the decimal point moved..

As fractions: `0.4 = 4/10 = 4xx10^-1" "larr` one decimal place

`0.04 = 4/100 = 4/10^2 = 4 xx 10^-2" "larr` 2 decimal places

`0.004 = 4/1000= 4/10^-3" "larr` 3 decimal places

and so on until

`0.0000004 = 4/10000000 = 4/10^7`

`4/10^7 = 4 xx 10^-7" "larr` 7 decimal places