ANSWER
-18.11
EXPLANATION
We want to find the mean of the probability distribution.
To do that, we apply the formula:
[tex]\mu=\Sigma\mleft\lbrace X\cdot P(X)\mright\rbrace[/tex]This means that we have to find the product of each value has its corresonding probability and find the sum:
[tex]\begin{gathered} \mu=(-20\cdot0.39)+(-19\cdot0.02)+(-18\cdot0.18)+(-17\cdot0.22)+(-16\cdot0.1)+(-15\cdot0.09) \\ \mu=(-7.8)+(-0.38)+(-3.24)+(-3.74)+(-1.6)+(-1.35) \\ \mu=-18.11 \end{gathered}[/tex]That is the mean of the probability distribution.
