Question

关于二项分布的题,设X∽B(2,p),Y∽B(3,p),且已知P(X≥1)=5/9 ,求P(Y≥1).

Answer 1

5/9=P(X≥1)=1-P(X=0)=1-(1-p)^2

p=1/3

P(Y≥1)=1-P(X=0)=1-(1-1/3)^3=19/27