Respuesta :
Answer:
a) For this case we define the random variable C as "cost of one telephone call". We know that we have two possible values for C 20 or 30 cents, so then we can define the probability mass function like this:
C | 20 30
P(C) | 0.6 0.4
b) [tex] E(C) = \sum_{i=1}^n C_i P(C_i)[/tex]
We know that :
[tex] P(C= V = 20) = 0.6 , P(C= D=30)=0.4[/tex]
If we replace we got:
[tex] E(C)= 20*0.6 + 30*0.4 = 24[/tex]
So then the expected value for the random variabe of interest C is 24 cents.
Step-by-step explanation:
Part a
For this case we define the random variable C as "cost of one telephone call". We know that we have two possible values for C 20 or 30 cents, so then we can define the probability mass function like this:
C | 20 30
P(C) | 0.6 0.4
Part b
In statistics and probability analysis, the expected value "is calculated by multiplying each of the possible outcomes by the likelihood each outcome will occur and then summing all of those values".
And the definition for the expected value is given by:
[tex] E(C) = \sum_{i=1}^n C_i P(C_i)[/tex]
We know that :
[tex] P(C= V = 20) = 0.6 , P(C= D=30)=0.4[/tex]
If we replace we got:
[tex] E(C)= 20*0.6 + 30*0.4 = 24[/tex]
So then the expected value for the random variabe of interest C is 24 cents.
