Answer
$\overline{x}=81.\overline{6}$
Work Step by Step
The mean $\overline{x}$ of a set of data with $n$ values can be found using the formula:
$\overline{x} = \dfrac{\sum{x}}{n}$ (sum of all the items divided by the number of values).
Solve for the mean using the formula above to obtain:
$\overline{x}=\dfrac{100+100+90+30+70+100}{6} = \dfrac{490}{6} = \dfrac{245}{3} = 81.\overline{6}$