First Year ICS Statistics Chapter 7 Online MCQ Test (Random Variables)

The probability of continuous random variable at x = a is__________.

• One A
• Zero B
• Between C
• More then one D

If the random variable x denotes the number of heads when three distinct coins are tossed, the x assumes values

• 0, 1, 2, 3 A
• 1, 3, 3, 1 B
• 1, 2, 3 C
• None of these D

For two independent random variables, Var(x) = 14 and Var(Y ) = 5, then var (X-y) is equal to.

• 9 A
• 70 B
• 19 C
• None of these D

The coins are tossed, the porbability of two tails is euql to.

• 1/2 A
• 1/4 B
• 3/4 C
• 1 D

The Area of trapezoid is equal to:

• sum of paralled sides x base A
• sum of paralled sides x base/2 B
• 2 x base x sum of paralled side  C
• Sum of paralled sides x base/4 D

If a Vann diagram is drawn for events A and B which are mutually exclusive, which f the folloiwng would always be true of A and B.

• Theire parts of the rectangle will overlap A
• Their parts fo the rectangle will be equal in area B
• Their parts of the rectangle will not overlap C
• None of these D

E(y-μ) is equal to

• E(y) A
• μ B
• zero C
• y-μ D

• y₁ = y₂ A
• Y₁ > y₂ B
• 
  C
• None of these D

If one event is unaffected by the outcome of another event, the two events are said to be

• Dependent A
• Independent B
• Mutually exclusive C
• Both b and c D

The probability of getting one red ball from a bag constaining 4 red, 3 white and 3 black balls is.

• 3/10 A
• 1/5 B
• 2/5 C
• 1/2 D

Variance of σ² is equal E to (Y²) - _______?

• E (y) A
• [E(y)]² B
• E(y²) C
• None of these D

A probability function is _________ function.

• Mathematical A
• Mathematical expectation B
• Converges C
• None of these D

F(y₁) ≤ F(y₂) if

• y₁= y₂ A
• Y₁>y₂ B
• y₁≤y₂ C
• y≥1/2 D

If x and y are independent random variables, E(xy)

• E(XY) A
• xE(y) B
• E(XY) C
• E(X) . E(Y) D

Coefficient  of variation (C.V) is given below

• Mean /S.D x10 A
• Mean/S.D x 100 B
• S.D/Mean x 100  C
• S.D/ Mean  D

What is the probability that a value chosen at random from a particular population is larger than the median of the popultion.

• 0.25 A
• 0.5 B
• 1.0 C
• 0.67 D

If two coins are tossed, the probability of getting one head and one tail is.

• 1/4 A
• 2/4 B
• 3/4 C
• 2/3 D