Answer:
They are not independent
Step-by-step explanation:
Given
E = Occurrence of 1 on first die
F = Sum of the uppermost occurrence in both die is 5
Required
Are E and F independent
First, we need to list the sample space of a roll of a die
[tex]Event\ 1 = \{1,2,3,4,5,6\}[/tex]
Next, we list out the sample space of F
[tex]Event\ 2 = \{2,3,4,5,6,7,3,4,5,6,7,8,4,5,\[/tex]
[tex]6,7,8,9,5,6,7,8,9,10,6,7,8,9,10,11,7,8,9,10,11,12\}[/tex]
In (1): the sample space of E is:
[tex]E = \{1\}[/tex]
So:
[tex]P(E) = \frac{n(E)}{n(Event\ 1)}[/tex]
[tex]P(E) = \frac{1}{6}[/tex]
In (2): the sample space of F is:
[tex]F = \{5,5,5,5\}[/tex]
So:
[tex]P(F) = \frac{n(F)}{n(Event\ 2)}[/tex]
[tex]P(F) =\frac{4}{36}[/tex]
[tex]P(F) =\frac{1}{9}[/tex]
For E and F to be independent:
[tex]P(E\ and\ F) = P(E) * P(F)[/tex]
Substitute values for P(E) and P(F)
This gives:
[tex]P(E\ and\ F) = \frac{1}{6} * \frac{1}{9}[/tex]
[tex]P(E\ and\ F) = \frac{1}{54}[/tex]
However, the actual value of P(E and F) is 0.
This is so because [tex]E = \{1\}[/tex] and [tex]F = \{5,5,5,5\}[/tex] have 0 common elements:
So:
[tex]P(E\ and\ F) = 0[/tex]
Compare [tex]P(E\ and\ F) = \frac{1}{54}[/tex] and [tex]P(E\ and\ F) = 0[/tex].
These values are not equal.
Hence: the two events are not independent
