In a certain game only one player can win and only one player always eventually wins. James, Austin, and Katelyn play this game together 3 times in a row. What is the probability that Katelyn wins at least one of the 3 games.?
(1) The probability that either James or Austin wins the game is 3/4
(2) James and Katelyn have an equal probability of winning the game.
OA is A
Given: Only one player can and only one eventually wins. J,A, and K play this game 3 times in a row.
Question: P(K wins at least one of the 3 games) = 1 - P(K wins none of the 3 games)
(1) P(K doesn't win) = 3/4
P(wins at least one of the 3 games) = 1 - (3/4 * 3/4 * 3/4)
Sufficient
(2) I am not sure why this is statement is not sufficient
J and K have an equal probability of winning the game. They play 3 games together. So, the
P(K wins) = 1/3
P(J wins) = 1/3
P(A wins) = 1/3
So, here i can figure out the probability that P(K wins at least one of the three games)
Not sure where i am wrong.
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In a certain game only one player can win and only one playe
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mbawisdom
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Your analysis of statement 1 is correct.vinni.k wrote:In a certain game only one player can win and only one player always eventually wins. James, Austin, and Katelyn play this game together 3 times in a row. What is the probability that Katelyn wins at least one of the 3 games.?
(1) The probability that either James or Austin wins the game is 3/4
(2) James and Katelyn have an equal probability of winning the game.
OA is A
Given: Only one player can and only one eventually wins. J,A, and K play this game 3 times in a row.
Question: P(K wins at least one of the 3 games) = 1 - P(K wins none of the 3 games)
(1) P(K doesn't win) = 3/4
P(wins at least one of the 3 games) = 1 - (3/4 * 3/4 * 3/4)
Sufficient
(2) I am not sure why this is statement is not sufficient
J and K have an equal probability of winning the game. They play 3 games together. So, the
P(K wins) = 1/3
P(J wins) = 1/3
P(A wins) = 1/3
So, here i can figure out the probability that P(K wins at least one of the three games)
Not sure where i am wrong.
For statement 2, you misread the statement and assumed that all three participants have an equal probability of winning. This isn't necessarily the the case. "James and Katelyn have an equal probability of winning the game" so P(J) = P(K). We don't know P(A). As a result, not sufficient.
Hope that helps.
