Answer:
(a) Name: Multinomial distribution
Parameters:
(b) Range:
(c) Name: Binomial distribution
Parameters:
Step-by-step explanation:
Given
High Slabs
Medium Slabs
Low Slabs
Solving (a): Names and values of joint pdf of X, Y and Z
Given that:
Number of voids considered as high slabs
Number of voids considered as medium slabs
Number of voids considered as low slabs
Since the variables are more than 2 (2 means binomial), then the name is multinomial distribution
The parameters are:
And the mass function is:
Solving (b): The range of the joint pdf of X, Y and Z
Given that:
The number of voids (x, y and z) cannot be negative and they must be integers; So:
Hence, the range is:
Solving (c): Names and values of marginal pdf of X
We have the following parameters attributed to X:
and
Hence, the name is: Binomial distribution
Solving (d): E(x) and Var(x)
In (c), we have:
and
In (b), we have:
However, the given values of x in this question implies that:
Hence:
This question implies that:
Because
--- for x
In (e), we have:
So:
In (a), we have:
So:
Expand
Using a calculator, we have:
So:
This implies that:
In (c), we established that X is a binomial distribution with the following parameters:
Such that:
So:
So:
Y has the following parameters
and