[tex]\begin{gathered} \text{ when we have a number in cientific notation and we want to convert it to decimal notation, } \\ \text{ we have to move the comma the number of places as the exponent of 10 tells us} \\ \text{the direction is given by the sign (- to the left, and + to the right)} \end{gathered}[/tex][tex]8.16\cdot10^{-4}=0.000816[/tex]
