HARD
Diploma
IMPORTANT
Earn 100

The discrete random variable X can take only the values 0, 1, 2, 3, 4, 5. The probability distribution of X is given by the following 

P(X=0)=P(X=1)=P(X= 2) = a

P(X=3)=P(X=4)=P(X= 5) = b

P(X2)=3P(X<2)

where a and b are constants.

Determine the values of a and b.

Important Questions on Valid Comparisons and Informed Decisions: Probability Distributions

HARD
Diploma
IMPORTANT

The discrete random variable X can take only the values 0, 1, 2, 3, 4, 5. The probability distribution of X is given by the following 

P(X=0)=P(X=1)=P(X= 2) = a

P(X=3)=P(X=4)=P(X= 5) = b

P(X2)=3P(X<2)

where a and b are constants.

Determine the probability that the sum of two independent observations from this distribution exceeds 7.

HARD
Diploma
IMPORTANT

The discrete random variables A and B are independent and have the following distributions.

a 1 2 3
PA=a 13 13 13
b 1 2 3
PB=b 16 23 16

The random variable C is the sum of one observation from A and one observation from B.

Show that P(C=3)= 518.

HARD
Diploma
IMPORTANT

The discrete random variables A and B are independent and have the following distributions.

a 1 2 3
PA=a 13 13 13
b 1 2 3
PB=b 16 23 16

The random variable C is the sum of one observation from A and one observation from B. Tabulate the probability distribution for C.

HARD
Diploma
IMPORTANT

When throwing a normal dice, let X be the random variable defined by X=the square of the score shown on the dice. What is the expectation of X?

HARD
Diploma
IMPORTANT

A "Fibonacci dice" is unbiased, six-sided and labelled with these numbers: 1, 2, 3, 5, 8, 13. What is the expected score when the dice is rolled?

HARD
Diploma
IMPORTANT

The discrete random variable X has probability distribution P(x)=x36 for x= 1, 2, 3,..... 8. Find E(X).

MEDIUM
Diploma
IMPORTANT

For the discrete random variable X, the probability distribution is given by

P(X=x)=kxx=1,2,3,4,5k10-xx=6,7,8,9 

Find the value of the constant k.

HARD
Diploma
IMPORTANT

For the discrete random variable X, the probability distribution is given by

P(X=x)=kxx=1,2,3,4,5k10-xx=6,7,8,9 

Find E(X).