Question

How to simplify `5 times 4.0 times 10^-4` in scientific notation?

Answer 1

`5xx4.0xx10^-4=2xx10^-3`

Explanation:

`5xx4.0xx10^-4`

Multiply `5xx4`.

`20xx10^-4`

Move the decimal to the left one place so that the coefficient has one non-zero digit in front of the decimal, and add `1` to the exponent.

`20xx10^-4=`

`2xx10^(-4+1)=`

`2xx10^-3`

Note: Since `5` has only one significant figure, and we are multiplying, the answer can have only one significant figure. Therefore, the coefficient must be `2` and not `2.0`, which has two significant figures.