Question 1026513
Let X = random variable for the score
PMF:
X=x       1   2    3      4      5     6
p(X=x)    0   0    0    0.50   0.40   0.10

==> E(X) = 1*0+2*0+3*0+4*0.50+ 5*0.40 +6*0.10 = 2+2+0.6 = 4.6, the mean of the distribution.