Probability and Statistics (3130006) MCQs

MCQs of Basic Probability

Showing 81 to 90 out of 108 Questions
81.

If x and y are two random variables, then E(x+y)=_______.

(a)

E(x.y)

(b)

E(x).E(y)

(c)

E(x)+E(y)

(d)

none of the above

Answer:

Option (c)

82.

V(x)=_______.

(a)

E(x)2-[E(x)]2

(b)

E(x2)-[E(x)]2

(c)

[E(x)]2-E(x2)

(d)

none of the above

Answer:

Option (b)

83.

If c is a constant, then V(c)=_______.

(a)

(b)

0

(c)

1

(d)

none of the above

Answer:

Option (b)

84.

If c is a constant, then V(cx)=_______

(a)

c·V(x)

(b)

c2·V(x)

(c)

V(x)

(d)

none of the above

Answer:

Option (b)

85.

If c is a constant, then V(x+c)=_______

(a)

V(x)

(b)

V(x)+c

(c)

c

(d)

none of the bove

Answer:

Option (a)

86.

If a and b are constants, then V(ax+b)=_______.

(a)

a·V(x)

(b)

a2·V(x)

(c)

a·V(x)+b

(d)

a2·V(x)+b

Answer:

Option (b)

87.

For a continuous random variable x, P(Xx)= _______.

(a)

-xf(t) dt

(b)

xf(t) dt

(c)

-xxf(t) dt

(d)

-f(t) dt

Answer:

Option (a)

88.

F(-)= _______.

(a)

0

(b)

1

(c)

(d)

none of the above

Answer:

Option (a)

89.

F(+)= _______.

(a)

0

(b)

1

(c)

(d)

none of the above

Answer:

Option (b)

90.

For F(x) which of following is true?

(a)

0F(x)1

(b)

0F(x)

(c)

-F(x)0

(d)

F(x)=0

Answer:

Option (a)

Showing 81 to 90 out of 108 Questions