If \(f(x)=\frac { 1 }{ 2 } \) ,\(E\left( { x }^{ 2 } \right) =\frac { 1 }{ 4 } \) then var(x) is _____________

(a)

0

(b)

\(\frac { 1 }{ 4 } \)

(c)

\(\frac { 1 }{ 2 } \)

(d)

1

In a binomial distribution,\(n=4,P(X=0)=\frac { 16 }{ 81 } \),then \(P(X=4)\) _____________

(a)

\(\frac { 1 }{ 16 } \)

(b)

\(\frac { 1 }{ 81 } \)

(c)

\(\frac { 1 }{ 27 } \)

(d)

\(\frac { 1 }{ 8 } \)

Var (2x ± 5) is =________

(a)

5

(b)

var (2x) ± 5

(c)

4 var (X)

(d)

0

A coin is tossed 3 times. The probability of getting exactly 2 heads is________

(a)

\(\frac { 1 }{ 2 } \)

(b)

\(\frac { 1 }{ 8 } \)

(c)

\(\frac { 3 }{ 8 } \)

(d)

\(\frac { 1 }{ 4 } \)

If the mean and S.D of a binomial distribution are 12 and 2 respectively, then ___________

(a)

npq = 4

(b)

\(q=\frac { 1 }{ 3 } \)

(c)

\(P=\frac { 2 }{ 3 } \)

(d)

\(pq=\frac { 1 }{ 9 } \)