Гипотезы
H_(i) - выбрана i-ая урна, i=1,2,3,4,5
p(H_(i))=1/5
A - вынут белый шар
p(A/H_(1))=p(A/H_(2))=1/4
p(A/H_(3))=p(A/H_(4))=p(A/H_(5))=2/4
p(A)=(1/5)*(1/4)+(1/5)*(1/4)+(1/5)*(2/4)+(1/5)*(2/4)+(1/5)*(2/4)=
=2*(1/5)*(1/4)+3*(1/5)*(2/4)=4/10=0,4