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You have a standard deck of cards consisting of the number cards 2,3,4,9, 10 plus J.Q. K. A inthe four different colours Diamond, Hearts, Spades and Clover. Assume that the cards are perfectlymixed, meaning that every sequence of the 52 cards is equally likely,We look at the following four events:

A₁: The uppermost card on the deck has colour Diamonds
A₂: The lowermost card on the bottom of the deck is a number card
A₃: The uppermost two cards on the deck have the same colour
a) Determine the probabilities Pr(A₁) Pr(A₂) Pr(A₃) of the three events.
b) Determine the probabilities of the events A₁∪ A₂, A₁ ∪ A₃ and A₂∪ A₃ Determine which of theseevents are independent.

User Ilyapt
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Final answer:

The probability of the topmost card being a diamond is 1/4, while the chance that the bottom card is a number is 9/13. The likelihood of the top two cards sharing the same color is 12/51. The union probabilities depend on whether events overlap and their individual probabilities, and in this case, A₁ and A₂ are not independent.

Step-by-step explanation:

The student asked to determine the probabilities of events A₁, A₂, A₃, and certain unions of these events within the context of a standard deck of 52 playing cards. The standard deck has four suits: clubs, diamonds, hearts, and spades, with each suit having 13 cards ranked from 2 to 10 plus Jack (J), Queen (Q), King (K), and Ace (A). Let's calculate these probabilities step by step.

Event A₁

The probability that the uppermost card on the deck is a diamond (Pr(A₁)) is 13/52 because there are 13 diamonds out of the total 52 cards. Therefore, Pr(A₁) = 1/4.

Event A₂

The probability that the lowermost card on the bottom of the deck is a number card (Pr(A₂)) is 36/52. This is because there are 9 number cards in each suit (2 through 10), totalling 36 number cards in the deck, so Pr(A₂) = 9/13.

Event A₃

The probability that the uppermost two cards on the deck have the same color (Pr(A₃)) requires considering that the first card can be any color. Once a card is drawn, there will be 12 cards of the same color remaining out of the 51 cards left. Thus, Pr(A₃) = 12/51.

Union of Events

For two events, A and B, the probability of their union (Pr(A ⋃ B)) is given by Pr(A) + Pr(B) - Pr(A ∩ B). However, determining whether the events are independent requires checking if Pr(A ∩ B) = Pr(A) × Pr(B). If the equation holds, the events are independent.

Without further steps, we can say that none of these events completely satisfies the criterion for independence. For example, A₁ and A₂ share no common outcome as cards cannot be both at the top and bottom simultaneously, which means they are not independent.

User DallonF
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