QUESTION A
The probability of an event is calculated using the formula:
[tex]P(E)=\frac{Number\text{ }of\text{ }favorable\text{ }outcomes}{Number\text{ }of\text{ }possible\text{ }outcomes}[/tex]There are 4 nines in a standard deck of cards. Therefore, there are 48 cards that are not nines.
Since there are 52 cards, the probability is calculated to be:
[tex]\begin{gathered} P=\frac{48}{52} \\ P=\frac{12}{13} \end{gathered}[/tex]The probability is 12/13.
QUESTION B
Odds in favor of a particular event are given by the number of favorable outcomes to the number of unfavorable outcomes. The formula is written out to be:
[tex]P(E)=\frac{Number\text{ }of\text{ }favorable\text{ }outcomes}{Number\text{ }of\text{ }unfavorable\text{ }outcomes}[/tex]Since we have that the number of favorable outcomes is 48 and the number of unfavorable outcomes is 4, we have that the odds in favor are given to be:
[tex]P=\frac{48}{4}=\frac{12}{1}[/tex]The odds are 12 to 1.