Question 1033567
(a) 1 - 0.09  - 0.11  - 0.24 -  0.25 -   0.12 -  0.08 = 0.11

(b) 1 - p(0) - p(1) = 1 - 0.09 - 0.11 = 0.8

(c)  {{{E(X) = 0*0.09 + 1*0.11 + 2*0.24 +  3*0.25 + 4*0.11 + 5*0.12 +  6*0.08 = 2.86}}}

(d) Now  {{{E(X^2) = 0^2*0.09 + 1^2*0.11 + 2^2*0.24 +  3^2*0.25 + 4^2*0.11 + 5^2*0.12 +  6^2*0.08 = 10.96}}}

==> {{{Var(X) = E(X^2) - (E(X))^2 = 10.96 - 2.86^2 = 2.7804}}}

==> {{{SD(X) = sqrt(2.7804) = 1.667}}}, to four significant figures.