Respuesta :

You have a 52 standard deck.

There are 4 suites on the deck: diamonds, hearts, spades, and clubs.

Each suite has 13 ranks: Ace, 2, 3, 4, 5, 6, 7, 8, 9, Jack, Queen, and King → This means that there are 4 cards with each rank on the deck.

The "9 of clubs is missing on your deck"

This means that:

1) Your deck has one less card, the total number of cards is 51.

2) Your deck has one less club, instead of 13 club cards, you have 12.

3) Your deck has one 9 less, which means that there are 3 nines on your deck.

a) You have to select one event, whose probability decreased due to the missing 9 of clubs.

For example, the event "you draw a card at random and it's a 9"

The expected probability of drawing a 9 of the deck can be determined as the number of nines divided by the number of cards on the deck:

[tex]\begin{gathered} P(9)=\frac{4}{52} \\ P(9)=\frac{1}{13} \\ P(9)=0.076\approx7.6\% \end{gathered}[/tex]

But in reality, there is one 9 is missing from the deck, so you have 3 nines and 51 cards on the deck, its probability is:

[tex]\begin{gathered} P(9)=\frac{3}{51} \\ P(9)=\frac{1}{17} \\ P(9)=0.059\approx5.9\% \end{gathered}[/tex]

The expected probability of drawing a card at random and the card being a 9 is 7.6%, but due to the missing card, the probability dropped to 5.9%.

This means that drawing a card at random and selecting a 9 is less likely than expected.

b) You have to select one event whose probability increased due to the missing card.

For example, the probability of drawing an Ace, knowing that the card is a club:

On a normal deck there are 13 clubs and "one Ace of clubs", the expected probability of drawing the ace, given that the card is a club can be determined as follows:

[tex]\begin{gathered} P(\text{Ace}|\text{Club)}=\frac{1}{13} \\ P(\text{Ace}|\text{Club)}=0.076\approx7.6\% \end{gathered}[/tex]

But we are missing one club, which means that the total number of clubs is missing, so instead of having 13 clubs, we have twelve. The probability can be determined as follows:

[tex]\begin{gathered} P(\text{Ace}|\text{Club)}=\frac{1}{12} \\ P(\text{Ace}|\text{Club)}=0.083\approx8.3\% \end{gathered}[/tex]

The expected probability of drawing the Ace, given that the card is a club, on a normal deck is 7.6%, but due to the missing 9 of clubs, this probability has increased to 8.3%.

So this event is more likely due to the missing card.

c) You have to select an event whose probability hasn't changed due to the missing card.

For example, the event "draw a card at random and is a Heart"

The expected probability of drawing a heart from the deck is equal to the quotient between the number of hearts and the total number of cards on the deck:

[tex]\begin{gathered} P(H)=\frac{13}{52} \\ P(H)=\frac{1}{4} \\ P(H)=0.25\approx25\% \end{gathered}[/tex]

Your deck is missing one card, so there are 13 Hearts and a total of 51 cards, the probability can be determined as follows:

[tex]\begin{gathered} P(H)=\frac{13}{51} \\ P(H)\approx0.254\approx25.4\% \end{gathered}[/tex]

The probability of drawing a heart is around 25% when the deck is complete or missing one card.